reconstructing precaution, deconstructing misconceptions

Reconstructing Precaution,Deconstructing MisconceptionsAlessandra Arcuri*

Myriad articles have been written about the precautionary principle;

some commentators have tried to clarify its content, others have

praised the principle, and still others have decried it and eventually

advocated for its repeal or nonadoption. The debate continues. The purpose of

this contribution is twofold: it aims to reconstruct a desirable version of the pre-

cautionary principle by identifying its constitutive elements, and to deconstruct

the most notable critiques of the principle by explaining the misconceptions

upon which these criticisms rest.

The discussion that follows warrants a brief introduction of the principle. In

its basic version, the principle holds that scientific uncertainty should not be

used to postpone (regulatory) action. While this may appear trivial, in practice it

is not. In fact, one problem of environmental decision-making in times of con-

tinuously evolving technologies is that uncertainty over the potential hazards of

new technologies can easily be used as arguments against regulation. This is all

the more true in situations where governments endorse deregulation as the pre-

ferred or default regulatory philosophy; in such circumstances, proponents of

regulation bear the burden of providing clear grounds of justification.

The escalation of bovine spongiform encephalopathy (BSE, also known as

Mad Cow Disease) in British cattle, which resulted in a national crisis, exempli-

fies the problems inherent in such a regulatory culture.1

The crisis originated in

1986 when the first cases of BSE were recorded in Britain. In spite of the rapid

escalation of the BSE epidemic in 1987, U.K. policy-makers did not take any

* I am indebted to two anonymous referees, the editorial staff of Ethics & International Affairs, Ellen Hey,

Giuseppe Dari Mattiacci, and Suja Suryanarayanan for helpful comments. Parts of this essay draw on: Alessan-

dra Arcuri, ‘‘The Case for a Procedural Version of the Precautionary Principle Erring on the Side of Environ-

mental Preservation,’’ in Marcel Boyer, Yolanda Hiriart, and David Martimort, eds., Frontiers in the Economics

of Environmental Regulation and Liability (Aldershot, U.K., and Burlington, Vt.: Ashgate, 2006), pp. 19–63; avail-

able as Global Law Working Paper 09 (2004) at www.nyulawglobal.org/workingpapers/GLWP_0904.htm; and

Alessandra Arcuri, ‘‘The Law of Catastrophic Risks: When the Impossible May Erupt into the Possible,’’ Ars

Aequi 55 (2006), pp. 2–10.

359

regulatory actions because the risks of cross-species transmissibility were deemed

unproven. In stark opposition to the spirit of the precautionary principle, scien-

tific uncertainty was used as a reason to postpone regulatory action.

Only after 1995, when for the first time humans contracted a new variant of

Creutzfeldt-Jakob Disease (vCJD) and the risk that BSE could cross species be-

came manifest, did U.K. officials and policy institutions respond to the emer-

gency. The response was rather late, though, not only in terms of human costs

and costs to agro-industry, but also in light of the disruption of public confi-

dence in official institutions that resulted thereafter. This example underscores

the point that the problem of postponing regulatory action because of uncertain-

ties is a real one. The implementation of the precautionary principle, in its basic

form, would have probably avoided or at least greatly contained the BSE crisis.

While the BSE crisis is a counterfactual example of the positive role the pre-

cautionary principle can play in risk regulation, the principle remains under fire.

Much controversy, I suspect, is fueled by a number of interrelated misconcep-

tions that are built into the debate about precaution. To gain some clarity on this

debate, it is crucial to recognize these misconceptions and deconstruct them. To

the best of my knowledge, such an analysis, notwithstanding the impressive

amount of literature concerning the principle, has yet to be done.2

This essay

will thus undertake the limited task of identifying and dispelling some of the

most common misconceptions.

Confusion and misconceptions are generated by the multiplicity of definitions

and interpretations of the precautionary principle, so I will begin with a short

discussion of the constitutive elements of the principle. The version suggested in

this essay is a mild one, according to which the precautionary principle should

be understood both (1) substantively, meaning that decisions should err on the

side of environmental preservation, and (2) procedurally, in the sense that dy-

namic decision-making processes should encourage learning practices, which in

turn would serve to decrease the level of uncertainty. Such decision-making pro-

cesses should also stimulate a dialogue among decision-makers, scientists, and

the regulated community. This understanding of the principle is in line with ba-

sic economic principles, and it is consequentialist in the sense that any precau-

tionary measures to be adopted following the principle are to be assessed in

relation to their effects. Thus understood, the principle should become the cor-

nerstone for the good governance of risk in contemporary societies.

360 Alessandra Arcuri

RECONSTRUCTING PRECAUTION BY RETHINKING ITSESSENTIAL ELEMENTS

Even if the debate about the precautionary principle is often portrayed as polar-

ized between pessimists and optimists, under closer scrutiny the central question

is more about what an appropriately formulated version of the precautionary

principle entails rather than about simply endorsing or rejecting it. In this re-

spect it is worth noting that though most critics reject the adoption of a general

principle of law named ‘‘the precautionary principle,’’ they concede that some

form of precaution is desirable. For instance, the well-known legal economic

scholar Cass Sunstein, while vehemently criticizing the precautionary principle,

supports a weak version of it, which he has renamed the ‘‘Irreversible and Cata-

strophic Harm Precautionary Principle.’’3

In this section, I briefly discuss the main constitutive elements of the precau-

tionary principle following a conceptualization of it defended in a previous es-

say.4

There, I suggested that it is theoretically possible to conceive of a spectrum

of versions of the precautionary principle that lie within two extremes: a Pre-

caution, that is, the absence of precaution; and Radical Precaution, that is, to ban

any activity that exposes society to uncertain risks irrespective of their potential

consequences. It is intuitive to see why these two extremes make little sense;

moreover, the positions of most scholars and most of the endorsements of the

principle in legal texts are not to be associated with such extremes. In this re-

spect, one can conclude that there is some agreement on what the precautionary

principle is not.

It is more difficult to find general agreement on a positive characterization of

the principle. One of the best-known formulations is found within Principle 15

of the 1992 Rio Declaration on Environment and Development: ‘‘Where there

are threats of serious and irreversible damage, lack of full scientific certainty shall

not be used as a reason for postponing cost-effective measures to prevent envi-

ronmental degradation’’ (emphasis added). While the principle as endorsed in

Principle 15 of the Rio Declaration is generally considered reasonable, several di-

mensions can be further specified. In the following I will outline the main con-

stitutive elements of the version of the precautionary principle that in my view

should be privileged. I group them in three blocks: conditions of applicability,

the substantive element, and the procedural element.

reconstructing precaution, deconstructing misconceptions 361

Conditions of Applicability

Let me begin by emphasizing that the principle is to be invoked not for any type

of risk but only in the presence of uncertainty. Uncertainty has a plurality of

meanings; for instance, authors have distinguished between legal, moral, institu-

tional, societal, situational, proprietary, and scientific uncertainty. The economic

notion of uncertainty is of particular interest here; it dates back to the well-

known economist Frank Knight, who has distinguished between measurable and

unmeasurable uncertainty, using the term ‘‘risk’’ to designate the former and the

term ‘‘uncertainty’’ for the latter: ‘‘The practical difference between the two cate-

gories, risk and uncertainty, is that in the former the distribution of the outcome

in a group of instances is known (either through calculation a priori or from sta-

tistics of past experience), while in the case of uncertainty this is not true, the

reason being in general that it is impossible to form a group of instances, because

the situation dealt with is in a high degree unique.’’5

Uncertainty in the Knigh-

tian sense is typically invoked with respect to the ignorance over the distribution

of probabilities of an outcome. In addition to uncertainty, there could be ambi-

guity, when the knowledge about the different outcomes is poor, or ignorance,

which implies absence of knowledge about the effects of an action. On top of

uncertainty, ambiguity, and ignorance, most agree that the precautionary princi-

ple is to be applied when potential negative outcomes are deemed serious and

irreversible.

Having clarified the conditions of applicability of the principle, I will now pin

down the other elements of the principle. In this respect, I have argued that

the precautionary principle should include both substantive and procedural

elements.

The Substantive Element

In substantive terms, decisions should err on the side of environmental preserva-

tion. This simple substantive criterion finds justification in mainstream eco-

nomic theory dating back several decades. The economists Kenneth Arrow and

Anthony Fisher analyzed the effects of uncertainty on the criteria for choosing

between two alternative uses of a natural environment—namely, preservation

and development.6

In short, they find that for decisions concerning dangerous

technologies with potentially irreversible consequences, the expected value of

benefits under uncertainty is less than the value of benefits under certainty.

‘‘An interpretation of this result,’’ the authors argue, ‘‘might be that, if we are


uncertain about the payoff to investment in development, we should err on the

side of underinvestment, rather than overinvestment, since development is irre-

versible.’’7

More recently, economists have tried to apply the theory directly

to the precautionary principle. The work of the economic scholars Christian

Gollier, Bruno Jullien, and Nicolas Treich is particularly significant.8

These

authors have used sophisticated models to show that ‘‘more scientific uncertainty

as to the distribution of a future risk—that is, a larger variability of beliefs—

should induce society to take stronger prevention measures today.’’9

In sum,

their model predicts that more uncertainty should induce society to leave more

options open for the future.

In this context it should also be stressed that there is no need to juxtapose en-

vironment and development, because measures to protect the environment

do not necessarily entail less, but rather ‘‘different,’’ development. Adopting a

bottom-line principle that is biased in favor of the environment can boost devel-

opment that is environmentally friendly. In this respect, the precautionary prin-

ciple can be seen as stimulating creativity and innovation.10

The set of theories reviewed reveal that the precautionary principle in its sub-

stantive dimension, demanding to err on the side of environmental preservation,

is informed by a sound economic rationale.

The Procedural Element

In relation to the procedural dimension, at least two issues need to be taken into

account: the role of time and the interplay among law, science, and democracy

that the principle demands. In relation to time, the legal scholars David Free-

stone and Ellen Hey have pointed out that ‘‘the new element is the timing of,

rather than the need for, remedial action’’11

(emphasis added). Emphasizing this

dynamic dimension of the principle means shifting the attention from the ques-

tion of what to do to when to take action—an essential question, given that post-

poning potentially damaging and irreversible decisions of development allows

learning processes, which are in turn crucial under conditions of uncertainty. Ac-

cordingly, the timing dimension entails that decision-making under the precau-

tionary principle is iterative and informative. This means that evaluative

procedures should be regularly repeated (iterated) and should be conducted

within an institutional framework that allows for the production and evaluation

of new information (informative).


In addition, a balanced interpretation of the principle must attend to the delicate

relationship between science and the law. The precautionary principle links science

and the law by requiring that some forms of scientific scrutiny are necessary for de-

cisions under conditions of uncertainty and disagreement over risk and potential

harm. It is important to emphasize that this requirement is not idiosyncratic with

respect to the precautionary principle; rather, it is fundamentally the same as in

other cases where specific scientific knowledge is integral to decision-making prin-

ciples, including the preventive and polluter-pays principles. Yet only the precau-

tionary principle has been criticized for being unscientific—a judgement, as I will

argue later in this paper, that derives from a reductivist conception of science.

A properly formulated precautionary principle should link science to the law

in an eminently procedural way. To put it simply, scientific assessments of risks

must be performed, but these assessments should not dictate decisions; they

should be more modestly conceived as providing information for the responsible

decision-makers. If risk assessment (broadly conceived to include various types

of scientific appraisals of risks) is to become a stepping-stone of precautionary

decision-making, the policy decisions about safety should not be taken by so-

called experts. Delegating policy decisions to scientists can, indeed, be justified

only by a mistaken conception of science, an issue discussed at length below. To

reach acceptable decisions in precautionary decision-making, some form of dem-

ocratic participation is instead necessary. It remains a challenge, however, to find

the appropriate institutional structures to render precautionary decision-making

democratic yet not subject to ill-informed or uninformed populist pressures.

In practice, further articulation of the procedural dimension of the principle

requires an analysis of the context in which the principle is adopted and imple-

mented; procedures would differ, for instance, depending on whether the princi-

ple were to be employed at the international or national level. For the present

purposes, then, it suffices to say that the procedural dimension of the principle

should favor decision-making processes that are iterative and informative over

time and that integrate experts’ assessments of the risks to be governed and peo-

ple’s preferences and values.

DISPELLING SOME COMMONMISCONCEPTIONS

Having clarified the constitutive elements of the principle, I now turn to com-

mon misconceptions of the precautionary principle and show how they can be


dispelled. Some detractors criticize the principle for its lack of clarity, while

others oppose it on normative grounds.12

I show below, however, that these

criticisms are largely rooted in several fundamental misconceptions about the

principle, and especially about the principle in relation to existing approaches to

risk regulation.

Misconception # 1: Precaution Is Paralyzing

An important criticism of the precautionary principle is that it is paralyzing.

This critique has been articulated by Cass Sunstein in several papers, as well as in

his Laws of Fear: Beyond the Precautionary Principle,13

and applies when the pre-

cautionary principle is understood to mean that ‘‘regulation is required whenever

there is a possible risk to health, safety, or the environment, even if the support-

ing evidence remains speculative and even if the economic costs of regulation are

high.’’14

Building on this formulation of the principle, Sunstein argues that ‘‘the

real problem is that the principle offers no guidance—not that it is wrong, but

that it forbids all courses of action, including regulation. It bans the very step

that it requires.’’15

His reasoning is that regulatory actions aimed at the gover-

nance of risks are likely to create other risks. For instance, a ban on the use of

saccharin aimed at reducing cancer risks may cause the increase of other risks re-

lated to the intake of sugary foods, such as the risk of obesity, cardiovascular dis-

ease, and diabetes. In addition to the emergence of substitute risks, the adoption

of safety regulations give rise to costs, which according to some economists can

be equated to the loss of human lives. In other words, regulatory costs entail

mortality risks, albeit indirectly. ‘‘If the principle argues against any action that

carries a small risk of imposing significant harm, then we should be reluctant to

spend a lot of money to reduce risks, simply because those expenditures them-

selves carry risks. Here is the sense in which the Precautionary Principle, taken for

all that it is worth, is paralyzing: It stands as an obstacle to regulation and non-

regulation, and to everything in between’’16

(emphasis added).

Sunstein’s reasoning follows a rigorous logic, providing what appears to be

one of the most powerful critiques of the principle. His reasoning is based on a

wrong premise, however—that is, on a radical and misconceived definition of

the principle. Indeed, his conceptualization of the principle appears to fit the

category of Radical Precaution, which, as noted above, is inappropriate and

not useful. The problem is that Sunstein argues that ‘‘this understanding of

the Precautionary Principle fits with the understanding of its most enthusiastic


proponents, and with relatively modest variations, this understanding fits with

many of the legal formulations as well.’’17

Such a claim is not supported by em-

pirical evidence, however; to the contrary, many important legal formulations

clearly depart from such an extreme interpretation, as I detail below.

First of all, most versions of the principle require that precautionary measures

be taken in cases of uncertain harm, which is obviously different from and less re-

strictive than automatically mandating an activity ban; nor do measures have to

be taken without regard to costs. Precautionary measures can indeed take many

forms. For instance, lowering speed limits, adding stop signs and traffic lights,

and requiring vehicle safety inspections can be seen as precautionary measures;

banning the circulation of motor vehicles altogether is surely not the only pre-

cautionary measure available to reduce the risk of traffic accidents.

Second, one crucial feature of many formulations of the principle is that sci-

entific uncertainty should not be used as an excuse to fail to take appropriate

precautionary measures in a timely manner. Next, and perhaps most promi-

nently, many legal instruments refer to ‘‘threshold conditions’’—such as the seri-

ousness of the threat and the irreversibility of its potential harm—that should

exist before the precautionary principle can be applied. Besides Principle 15 of

the Rio Declaration, which is per se one of the most widely accepted formula-

tions of the principle at the international level, other formulations adhere to a

similar understanding of the principle; to name just a few, Article 2.5 (jointly

read with Article 1.2) of the 1992 Helsinki Convention on the Protection and Use

of Transboundary Watercourses and International Lakes, Article 3.3 of the 1992

UN Framework Convention on Climate Change, and the preamble of the 2000

Cartagena Protocol on Biosafety to the Convention on Biological Diversity.

In short, the paralysis critique makes sense only if one defines the precaution-

ary principle in an extreme and radical way—a definition that is hard to find in

most legal texts.

Misconception # 2: Cost-Benefit Analysis Is Superior to Precautionas a Paradigm for Risk Regulation

Several legal-economic authors have argued that cost-benefit analysis (CBA) of

regulation is superior to the precautionary principle as a policy-making tool.18

Here I suggest that the opposite is true. CBA is not desirable or appropriate

when conditions of uncertainty obtain.19

The grounds to reject CBA are mainly

procedural, yet they are intrinsically related to substantive questions. Indeed, to


understand why CBA is to be opposed on procedural grounds, one should begin

by discussing the substantive grounds for opposing or endorsing CBA under

conditions of uncertainty.

Under conditions of uncertainty, costs and benefits cannot be calculated in a

way that accounts adequately for potential outcomes and the harms those out-

comes might produce. Advocates of CBA note that such methodologies as the

Delphi method, sensitivity analysis, Monte Carlo analysis, and, more generally,

Bayesian updating can help the analyst to deal with uncertainty, and that there-

fore CBA can still be employed.20

While these techniques are highly developed

and used in a variety of contexts to account for uncertainties, they are by

no means a crystal ball. There are many risks associated with using them as a

remedy for those cases in which calculating costs and benefits would otherwise

be impossible.

Most prominently, the ultimate result of CBA is a number expressing the net

benefits in monetary terms; no matter how clearly all the uncertainties are stated

in the analysis, there is a very high danger that this number is branded as the

only answer to the policy question. A clear example of the powerful, and yet

dangerous, rhetoric of numbers in the context of regulatory policy is provided

by the legal scholar Lisa Heinzerling, who has studied the use of the widely cited

table drafted by the economist John Morrall, which lists the costs per life saved

of various types of risk-reducing regulation.21

The table’s numbers depended on

a set of questionable assumptions. What is puzzling is that even authors who ex-

plicitly reject those assumptions have relied on the table’s numbers to criticize

regulation. The interesting point is that the process by which the numbers are

generated is too easily forgotten. In the case of Morrall’s table, something as fun-

damental as the discount rate was overlooked. How plausible is it then to expect

that a rational discussion would emerge on the implementation of the Delphi

method (surely a far more technical issue than the choice of a discount rate)? In

short, very sophisticated methods originally conceived to deal with uncertainties,

when embodied in a policy-making tool such as CBA, may turn out to obscure

the debate rather than clarify it.

The issue of uncertainty and CBA has been taken up also by authors who have

more specifically criticized the use of Bayesian updating as a means to rehabili-

tate CBA under conditions of uncertainty. The distinctive feature of this method

is to assign subjective probabilities; the problem, however, is that Bayesian

theory does not tell how to build the initial subjective probabilities. This leaves


room for highly discretionary choices. As put by Martin O’Connor and others,

‘‘. in practice the employment of the Bayesian approach amounts to adoption

of an ‘empty box.’ Depending on the subjective probabilities and states of the

world incorporated into the calculations, the procedure may serve to legitimate

decisions that are substantially arbitrary.’’22

While it is possible to use some methodologies to address uncertainties, pre-

dicting outcomes is gravely inaccurate, if not unfeasible, under conditions of

uncertainty. The emphasis placed on numbers by the technique of CBA is,

accordingly, questionable. At a higher level of abstraction, something that is sub-

stantively manageable becomes procedurally unacceptable. This suggests that the

attention should be shifted from the best outcomes to the best ways of reaching

decisions.

This does not mean that costs and benefits should be neglected. It does mean,

however, that where uncertainty and/or ignorance are dominant, all the steps in

the process of decision-making should be made explicit and be at the center of

attention. The process should guarantee that different stakeholders are allowed to

contribute to the creation of knowledge in the decision-making process, enhanc-

ing transparency and reducing the risk of regulatory capture. Most notably,

the muddled relationship between facts and values, typical of decisions concern-

ing serious risks, should not be hidden behind the veil of the objectivity of dry

numbers.

CBA versus Maximin?

Another more subtle misconception is the idea that the only alternative to CBA

is a maximin strategy. While the former maximizes expected benefits, the latter

decision rule is more cautious, ‘‘maximizing’’ the worst outcome. Maximin may

lead to welfare-inferior outcomes and sometimes to intuitively absurd ones,

and for this it has been attacked.23

On the other hand, a strong argument can

be made that in at least some types of cases a decision rule maximizing the

worst-case outcome is the more appropriate one. If probabilities are not known,

calculations of expected benefits must necessarily depend upon questionable

assumptions, thus making it impossible to achieve a realistic sense of what the

net outcomes would be.24

In an illuminating contribution, Stephen Gardiner has argued that a core ver-

sion of the precautionary principle could be designed around the Rawlsian maxi-

min principle.25

According to Rawls the maximin strategy is plausible when three


conditions are met: when the knowledge about outcomes’ probabilities is absent

(that is, uncertain), when the chooser cares little for the foregone gains, and

when the worst-case scenario involves ‘‘grave risks.’’ This conceptualization of the

precautionary principle appears rather convincing because it applies a balanced

version of the maximin decision-making rule. While I agree that a Rawlsian max-

imin rule of the type suggested by Gardiner may be a useful analytical tool to give

more body to the substantive dimension of the precautionary principle, I believe

that by focusing on decision rules of this sort an important part of the under-

standing of the precautionary principle is missed.

The precautionary principle, as I have argued it should be formulated, is

richer than both CBA and maximin. In contrast to both, precautionary decision

rules are informed by both substantive and procedural rationality. Herbert

Simon, the first to use this distinction, has poignantly argued that in a world char-

acterized by uncertainties and complexities, ‘‘we must give an account not only

of substantive rationality—the extent to which appropriate actions are chosen—

but also procedural rationality—the effectiveness . of the procedure used to

choose actions. As economics moves out toward situations of increasing cogni-

tive complexity, it becomes increasingly concerned with the ability of actors to

cope with the complexity, and hence with the procedural aspects of ration-

ality.’’26

Because of the complexities and uncertainties that characterize the cir-

cumstances under which the precautionary principle is invoked, it is not

satisfactory to limit the discussion to issues of substantive rationality.

In fact, Gardiner concedes the necessity of a procedural interpretation of max-

imin, noting that ‘‘in order to judge whether the Rawlsian conditions are met we

need to decide, amongst other things: what it takes to lack probability informa-

tion, or for such information to be deemed unreliable; what counts as caring lit-

tle for gains; and what constitutes an unacceptable outcome.’’27

Indeed, we must

have procedures to determine, for example, what constitutes an ‘‘unacceptable

outcome’’ or ‘‘grave risk.’’ Procedures, including opportunities for public partic-

ipation, are necessary to determine what risks are considered grave and un-

acceptable by society. In addition, both maximin and CBA yield only a static

solution to a problem by indicating what decisions should be taken at a certain

point in time; neither criteria offer guidance on how to cope with changes in

knowledge. Procedures such as the iterative and informative aspects of the prin-

ciple, as outlined above, enable decision-making to decrease uncertainty and to

take into account knowledge changes.


Misconception # 3: The Worst-Case Scenario Is Impossible

‘‘Man can believe the impossible but can never believe the improbable.’’

—Oscar Wilde

As argued, the precautionary principle is appropriately applied with respect to

activities or products posing serious threats to the environment or citizens’ health

and safety. Such serious threats are often associated with worst-case scenarios,

which in turn are rather unlikely to occur. Many risk analysts have endorsed the

position that hazards below a certain probability threshold should be ignored.

The philosopher of science Kristin Shrader-Frechette has labeled this approach

the ‘‘probability-threshold’’ or ‘‘de minimis’’ position.28

Those holding such a

position criticize the precautionary principle as disproportionately focused on

worst-case scenarios.

To be sure, the precautionary principle does not require that all worst-case

scenarios should be given the same weight, because this would surely lead to

paralysis by analysis. Let us consider, for example, a small country that has to

decide on the regulation of airplane traffic and on the agricultural use of geneti-

cally modified organisms (GMOs). In the first case, notwithstanding an already

highly regulated environment, it is not possible to rule out that in the worst-case

scenario a plane accident could occur causing the death of all passengers.

Allowing the agricultural use of GMOs would generate, in the worst-case sce-

nario, an ecological disaster. The government of this country, by following the

precautionary principle, can legitimately decide to give different weights to these

two worst-case scenarios, accepting, for instance, the first hazard but not the sec-

ond. In the first case, in fact, the risk could be considered acceptable because it

is voluntarily undertaken by people who decide to travel by plane; in addition,

the benefits of traveling by plane are considered high enough to justify the

risk. In the second instance, by contrast, the risk is considered unacceptable

because it is involuntarily borne by society; modified foods cannot be adequately

tracked or segregated, and so some people will consume them unwittingly.

Moreover, if we assume that this small country already has an adequate

agricultural base, the foregone benefits from banning the biotechnology are not

great.

As seen, the procedural side of the precautionary principle requires the imple-

mentation of democratic decision-making processes that would help the decision-

maker to select and prioritize risks. The point here is that a criterion of selection


according to which highly improbable risks should be disregarded, as the propo-

nents of the probability-threshold position advocate, is simply wrong.

Shrader-Frechette has already discussed several arguments showing why the

probability-threshold position rests on shaky foundations. One problem with

this position is that it neglects risk trade-offs. By focusing on the probability di-

mension of the problem only, the types and magnitude of the harms as well as

the benefits deriving from the activity posing the risks are entirely disregarded.

For instance, an activity that poses a small threat of serious injury for society

might be deemed unacceptable because the benefits stemming from that activity

are zero or very unevenly distributed. In other words, the acceptability of risks

cannot be judged on the basis of probability only.

Yet in the case of the precautionary principle, a stronger argument comes to

mind—namely, that we are under the conditions of uncertainty; thus, even when

an event is considered rather unlikely, the objective probability distribution is

not known and, accordingly, to set a threshold becomes a somewhat arbitrary

decision of the policy-maker.

There is another reason why it is important to pay attention to improbable

harms with potential catastrophic consequences. According to the research of

the social scientist Max Bazerman, there is a strong tendency to underestimate

worst-case scenarios, which leads society to so-called ‘‘predictable surprises: an

event that leads an organization or nation to react with surprise, despite the fact

that the information necessary to anticipate the event and its consequences was

available.’’29

A vivid example of the tragic underestimation of worst-case scenar-

ios is given by the history of the 1984 disaster at the Union Carbide plant that kil-

led between 3,000 and 20,000 people in Bhopal, India. Although a report of the

health inspectors from the Union Carbide Institute in West Virginia had warned

that a runaway reaction could occur in Bhopal, then CEO Warren Anderson dis-

missed the hypothesis as ‘‘a worst-case scenario’’!30

Drawing on previous studies, Max Bazerman has identified the roots of pre-

dictable surprises in psychological mechanisms and in organizational and politi-

cal barriers. In relation to the former, people tend to have positive illusions and

extremely high discounting of the future, which results in assigning much greater

value to present outcomes than to future ones, thus discouraging measures that

yield benefits in the distant future. Organizational and political barriers include

the existence of dysfunctional incentives to take precautionary measures and

exposure of the policy-making establishment to deep-pocket special-interest


groups. From this perspective the precautionary principle may be seen as a basis

to counter existing barriers and thereby to avoid predictable surprises. The focus

of the precautionary principle on so-called worst-case scenarios can, then, be

conceived as a strategy to mitigate the effects of tendencies to ignore risks judged

to be remote.

Misconception #4: The Precautionary Principle Is Unscientificand Science Is a Neutral Arbiter

The precautionary principle has been widely stigmatized for being ‘‘unscien-

tific.’’31

A case in point is the BSE crisis discussed in the introduction, where the

reluctance of British policy-makers to implement the principle was due to the be-

lief that it lacked scientific foundation. For instance, when in 1989 under the

pressure of European institutions a first timid precautionary measure, a specified

bovine offal (SBO) ban, was adopted, ‘‘it was frequently stressed by politicians

and civil servants alike that the SBO ban, where the precautionary principle was

applied, was considered as ‘going over the top, going to be too restrictive,’ for a

lack of scientific evidence to support that regulation.’’32

The EU Committee of the American Chamber of Commerce presented a simi-

lar criticism of the precautionary principle in a paper on risk analysis; they ar-

gued that the precautionary principle should be rejected for various reasons,

including the fact that it ‘‘did not constitute a scientific principle.’’33

In 2001, a

scientist from the United States Environmental Protection Agency’s (EPA) Office

of Water portrayed the precautionary principle as ‘‘the application of junk sci-

ence.’’34

Henry Miller, the founding director of the EPA’s Office of Bio-

technology, also decried the application of the principle for resulting in

unscientific policies.35

Several scholars, including scientists and philosophers of

science, have variously rebutted the argument that the precautionary principle is

founded on flawed science.36

The criticism of the precautionary principle as ‘‘unscientific’’ rests on the naıve

belief that science has unequivocal answers to policy problems or, relatedly, that

science is a neutral arbiter of disagreements over policy-making issues. Science is

neither unequivocal nor suited to answer policy questions. To understand this

point we need to understand the practice of risk assessment and its inherent

limits.

The estimation of a probability of some harm does not tell us when a product

is safe; in other words, the vexed question, How safe is safe enough? transcends


the domain of science and requires that judgment be brought to bear in

decision-making. For example, estimating that the annual mortality risk for

people living within 100 miles of a chemical factory is 1/100,000 higher than that

of an average person living in the same country does not answer the question of

whether it is safe to live near that chemical factory; nor does it tell us whether a

specific safety regulation is needed to reduce that risk or whether it is appropri-

ate to compensate the people living nearby. To answer these types of questions,

many factors unrelated to the probability of harm need to be understood, such

as the acceptability of a particular typology risk, its distribution, the benefits

accruing to the population that is bearing the risk, and so on.

Moreover, when scientists assess the potential risks of certain substances or

technologies, they often disagree. When risk assessments are characterized by sci-

entific uncertainties, it is possible that conflicting hypotheses are all plausible. A

plausible hypothesis has been defined as ‘‘one that we believe to be at least possi-

ble and worthy of further testing. That is, the hypothesis is not just logically pos-

sible but it is a serious possibility, given our corpus of knowledge’’37

(emphasis

added). It goes without saying that the precautionary principle applies only when

the hypothesis of the occurrence of a certain hazard is scientifically plausible. In

the case of carcinogenic risk assessment, for example, animal bioassay (testing the

response of animals, usually rodents, to hazardous substances) is a widely used

method to estimate the probability of developing cancer from exposure to those

substances. Extrapolating data from animals to humans is a complex and delicate

process.38

One major problem is how to extend the dose-response curve from

the high doses to which animals are exposed in the laboratory to the lower doses

to which humans are exposed in the environment. There are several plausible

models for fitting the animal data and extrapolating the dose-response curve to

low doses: ‘‘at least half a dozen tractable mathematical models can be used with

experimental bioassay data. Generally, they all fit such data fairly well and have

some bases in cancer biology.’’39

Thus, these models, while all plausible, when

used to extrapolate data from animals to humans will likely provide different an-

swers to the same human safety question. Simply put, in the practice of risk as-

sessment several methodological choices need to be made, including what model

should be used to extrapolate data, what risks should be studied, whether cumu-

lative effects should be studied, and so on. These decisions, taken at different

stages of the scientific assessment, are likely to lead to different results.


When scientific assessment yields multiple answers to the same problem, how

can one science-based decision be judged better than another? Even if we believe

that there is a ‘‘true’’ answer ex post, at the moment of the decision we necessarily

lack the information to conclude that there is one ‘‘best’’ decision. The best deci-

sion would, indeed, depend on the ‘‘best’’ science; however, if our assumption is

that there is controversy within an established scientific environment, we cannot

assert, by definition, that there is a ‘‘best’’ science ex ante. Therefore, it is not in

the substantive dimension of the question that we can find an answer. Given the

circularity of the problem, we must develop procedures to determine the ‘‘best

way’’ to take decisions on the basis of controversial science. This does not imply

that attempts at better scientific understanding of the problems are to be aban-

doned, but rather that science alone cannot offer a solution because it does not

provide unequivocal answers. The use of science as a dictator of policy solutions

is neither viable nor desirable.

In short, the critique that the precautionary principle is unscientific rests on a

somewhat simplified account of science and pays a disservice to scientific pro-

gress rather than contributing to it. In its more basic version, the precautionary

principle simply allows the policy-maker to take into account plausible hypothe-

ses of risks seriously threatening society and to act upon this information.

Misconception #5: Fear and Irrationality Are the Driving ForcesBehind the Precautionary Principle

‘‘A restoration of faith in scientific rationality is possible—but only if the scientific

establishment is prepared to concede that unreason might well have its reasons.’’40

—Pat Kane

Let me conclude this journey into the misconceptions about the precautionary

principle by coming back to Sunstein’s Laws of Fear, in which he argues that the

precautionary principle ‘‘becomes operational if and only if those who apply it

wear blinders; that is, if they focus on some aspects of the regulatory situation

but downplay or disregard others.’’41

He further identifies the blinders that un-

derlie the application of the principle in people’s cognitive limitations, including

availability heuristics, probability neglect, and loss aversion. Resting on the as-

sumption that people perceive risks in an erroneous and irrational way, Sunstein

suggests an alternative: a system in which decisions are adopted on the basis of

experts’ judgments only.42

This might be persuasive if we believe that people’s


cognitive limitations are all that lie behind the precautionary principle, and that

the lay public is irrational to the point that their preferences should be dis-

regarded. But we have good reasons to believe that such is not the case. While it

has been widely shown that laypeople make systematic mistakes in assessing

risks,43

it is simplistic to conclude that because of these systematic mistakes the

lay public is irrational. The fact that risk is ranked by experts and the lay public

in different ways can only partially be ascribed to errors. Most important, the

discrepancy in judgments is due to the fact that people rank risks not only on the

basis of the probability of the occurrence of an accident, but also in terms of

qualitative dimensions of risk.

A significant number of studies have shown that people often characterize

risks on the basis of some of the following qualitative dimensions: risk is volun-

tarily or involuntarily taken; risk is chronic or catastrophic; it is common or un-

common; it is known or unknown to those exposed; it is known or unknown to

science; it is old or new; it is controllable or uncontrollable by those exposed.44

These studies shed light on the reasons, beyond cognitive errors, that nonexperts

perceive risks in a different way than experts qua experts do, and thus it is diffi-

cult to disagree with the cognitive psychologist Paul Slovic, who concludes that

‘‘lay people sometimes lack certain basic information about hazards. Their basic

conceptualization of risk, however, is much richer than that of experts.’’45

Sunstein’s reliance on people’s irrationality to explain the operability of the

precautionary principle also leads him to overlook work that argues that prefer-

ences toward risks are significantly shaped by culture.46

Put differently, risk per-

ceptions are largely determined by one’s commitment to a particular lifestyle or

to ideals of good society. For example, several studies have shown that risk per-

ceptions ‘‘cohere across seemingly discrete issues. How likely one is to perceive

global warming to be a threat, for example, predicts how much one worries about

gun accidents.’’47

This phenomenon, called ‘‘belief clustering,’’ can easily be ex-

plained by a model that sees risk perceptions as an effect of cultural norms,

whereas the irrationality theory as endorsed by Sunstein cannot make sense of it.

In short, as Dan Kahan and others show, ‘‘once the influence of culture is taken

into account, what Sunstein sees as public hysteria is often revealed to be a com-

plex form of status competition between adherents of competing cultural

visions.’’48

Ignoring the fact that perceptions of risks are informed by a set of variables

richer than the probability set and the size of the damage is reductivist.


Of course, assuming that the lay public could without problem understand com-

plex and technical issues is equally reductivist. The challenge, then, is to find

concrete solutions in which the decision-maker responds to both the experts and

the lay public and where a communicative relationship is created among all the

parties affected by the decision.

PRECAUTION REHABILITATED

The precautionary principle has often been portrayed as the principle of neo-

Luddism, and the critiques reviewed in this essay contribute to such a portrayal.

As shown above, however, some criticisms are fueled by a reductivist conceptual-

ization of the principle, while others are stirred by an almost religious under-

standing of science, by a misplaced focus on optimal outcomes, and by a

stigmatization of the lay public as irrational or incompetent. As Ortwin Renn

observes, however, ‘‘society is not only concerned about risk minimization. Peo-

ple are willing to suffer harm if they feel it is justified or if it serves other goals.

At the same time, they may reject even the slightest chance of being hurt if they

feel the risk is imposed on them or violates their other attitudes and values. Con-

text matters. So does procedure of decision making independent of outcome. Re-

sponsive risk management needs to take these aspects into account’’49

(emphasis

added).

The precautionary principle, if understood both substantively and procedur-

ally, can serve as an important interface between science and the law in circum-

stances where uncertainties and risks of irreversible harms are present. Following

the principle, processes of learning are stimulated, and accordingly, technology

is not halted; to the contrary, application of the principle, particularly in its iter-

ative and informative aspects, is conducive to a better understanding of techno-

logical developments and their effects. In this sense the precautionary principle

is based on an economic and consequentialist approach and is not opposed

to innovation or technology. It simply requires consistent regard rather than dis-

regard for the risks inherent in innovation and technology, thus fulfilling a

requirement of good governance of our risk society.

NOTES1

For an account of the BSE crisis, read Patrick van Zwanenberg and Erik Millstone, ‘‘‘Mad Cow Dis-ease’ 1980s–2000: How Reassurance Undermined Precaution,’’ in European Environment Agency, LateLessons from Early Warnings: The Precautionary Principle 1896–2000, Environmental Issue Report 22(Copenhagen, Denmark: European Environment Agency, 2001), pp. 157–67.


2

A similar type of analysis, though focusing on a somewhat different set of problems, is to be found inPer Sandin, Martin Peterson, Sven Ove Hansson, Christina Ruden, and Andre Juthe, ‘‘Five ChargesAgainst the Precautionary Principle,’’ Journal of Risk Research 5, no. 4 (2002), pp. 287–99.

3

Cass R. Sunstein, ‘‘Irreversible and Catastrophic,’’ Cornell Law Review 91, no. 4 (2006), pp. 841–97;available at ssrn.com/abstract=705323; and Cass R. Sunstein, Laws of Fear: Beyond the PrecautionaryPrinciple (Cambridge, England: Cambridge University Press, 2005), ch. 5.

4

Arcuri, ‘‘The Case for a Procedural Version of the Precautionary Principle,’’ in Boyer, et al., Frontiersin the Economics of Environmental Regulation.

5

Frank H. Knight, Risk, Uncertainty, and Profit (Chicago: University of Chicago Press, 1921), p. 233.6

Kenneth Arrow and Anthony Fisher, ‘‘Environmental Preservation, Uncertainty, and Irreversibility,’’Quarterly Journal of Economics 88 (May 1974), pp. 312–19. See also Anthony Fisher, John Krutilla, andCharles Cicchetti, ‘‘The Economics of Environmental Preservation: A Theoretical and Empirical Anal-ysis,’’ American Economic Review 62 (September 1972), pp. 605–19; Kenneth Arrow, ‘‘Optimal CapitalPolicy and Irreversible Investment,’’ in James N. Wolfe, ed., Value, Capital and Growth: Papers inHonor of Sir John Hicks (Edinburgh: Edinburgh University Press, 1968); and Kenneth Arrow andMordecai Kurz, ‘‘Optimal Growth with Irreversible Investment in a Ramsey Model,’’ Econometrica38 (March 1970), pp. 331–44.

7

Similar results were found by Claude Henry, who coined the expression ‘‘irreversibility effect.’’ ClaudeHenry, ‘‘Investment Decision under Uncertainty: The Irreversibility Effect,’’ American EconomicReview 64 (December 1974), pp. 1006–12.

8

Christian Gollier, Bruno Jullien, and Nicolas Treich, ‘‘Scientific Progress and Irreversibility: An Eco-nomic Interpretation of the Precautionary Principle,’’ Journal of Public Economics 75 (February 2000),pp. 229–53. For a systematic survey of the economic literature focusing specifically on the precau-tionary principle, see Christian Gollier and Nicolas Treich, ‘‘Decision-Making under ScientificUncertainty: The Economics of the Precautionary Principle,’’ Journal of Risk and Uncertainty 27

(August 2003), pp. 77–103.9

The authors emphasize that ‘‘environmental problems deal with the management of a limited stockof a good. Varying this stock through early consumption generates an environmental externality forfuture generations.’’ They seem to be the first to deal not only with irreversibility but also withaccumulation phenomena (e.g., past emissions of CO

2increase current exposure to greenhouse risks

due to the accumulation of gas in the atmosphere). Ibid., p. 245.10

Technological innovation may be stimulated by regulation if companies will develop better strategiesto comply with regulatory requirements, and this in turn will increase societal wealth and health. Foran excellent analysis of this issue, see Samuel J. Rascoff and Richard L. Revesz, ‘‘The Biases of RiskTradeoff Analysis: Towards Parity in Environmental and Health and Safety Regulation,’’ University ofChicago Law Review 69 (Fall 2002), pp. 1778–80, 1809–11.

11

David Freestone and Ellen Hey, ‘‘Origins and Development of the Precautionary Principle,’’ in DavidFreestone and Ellen Hey, eds., The Precautionary Principle and International Law—The Challenge ofImplementation (The Hague: Kluwer Law International, 1996), p. 13.

12

Among the most influential critics of the principle, see Cass R. Sunstein, ‘‘Beyond the PrecautionaryPrinciple,’’ University of Chicago Law & Economics, Olin Working Paper No. 149 (January 2003);available at http://ssrn.com/abstract=307098; Sunstein, Laws of Fear; Lucas Bergkamp, ‘‘Understandingthe Precautionary Principle,’’ Environmental Liability 10 (2002), Part I, pp. 18–30, and Part II, pp. 67–82; Indur Goklany, The Precautionary Principle: A Critical Appraisal of Environmental Risk Assessment(Washington, D.C.: Cato Institute, 2001); and Richard B. Stewart, ‘‘Environmental Regulatory Deci-sionmaking under Uncertainty,’’ Research in Law and Economics 20 (2002), pp. 71–126.

13

Sunstein, Laws of Fear. This argument was initially articulated in Sunstein, ‘‘Beyond the PrecautionaryPrinciple’’; it can also be found in Robert W. Hahn and Cass R. Sunstein, ‘‘The Precautionary Principleas a Basis for Decision Making,’’ Economists’ Voice 2, no. 2, art. 8 (2005); available at ssrn.com/abstract=721122.

14

Sunstein, Laws of Fear, p. 2415

Ibid., p. 26.16

Ibid., p. 33.17

Ibid., p. 24.18

Sunstein, ‘‘Beyond the Precautionary Principle’’; Stewart, ‘‘Environmental Regulatory Decisionmakingunder Uncertainty’’; Hahn and Sunstein, ‘‘The Precautionary Principle as a Basis for Decision Mak-ing’’; and Richard A. Posner, Catastrophe: Risk and Response (New York: Oxford University Press,2005), ch. 3.

19

Let me stress from the outset that the following analysis will focus mostly on the concept ofuncertainty; however, it should be clear that similar conclusions would hold when ambiguity andignorance are present.

20

See, e.g., Stewart, ‘‘Environmental Regulatory Decisionmaking under Uncertainty.’’


21

Lisa Heinzerling, ‘‘Regulatory Costs of Mythic Proportions,’’ Yale Law Journal 107 (1998), pp. 1981–2070.

22

Martin O’Connor, Sylvie Faucheux, Geraldine Froger, Silvio Funtowicz, and Giuseppe Munda,‘‘Emergent Complexity and Procedural Rationality: Post-Normal Science for Sustainability,’’ in RobertCostanza, Olman Segura, and Juan Martinez-Alier, eds., Getting Down to Earth: Practical Applicationsof Ecological Economics (Washington, D.C.: Island Press, 1996), pp. 233–34.

23

John Harsanyi, ‘‘Can the Maximin Principle Serve as a Basis for Morality: A Critique of John Rawls’sTheory,’’ American Political Science Review 69, no. 2 (June 1975), pp. 594–606.

24

Kristin S. Shrader-Frechette, Risk and Rationality: Philosophical Foundations for Populist Reforms(Berkeley and Los Angeles, Calif.: University of California Press, 1991), ch. 8.

25

Stephen Gardiner, ‘‘A Core Precautionary Principle,’’ Journal of Political Philosophy 14, no. 1 (2006),pp. 33–60; for a comment on this point, see Sunstein, ‘‘Irreversible and Catastrophic,’’ pp. 35–54; andSunstein, Laws of Fear, pp. 111–15.

26

Herbert Simon, ‘‘Rationality as a Process and as a Product of Thought,’’ American Economic Review68, no. 2 (1978), p. 9.

27

Gardiner, ‘‘A Core Precautionary Principle,’’ p. 57.28

For a review of the group of scholars that would endorse this position, see Kristin S. Shrader-Frechette, ‘‘Technological Risk and Small Probabilities,’’ Journal of Business Ethics 4 (1985), pp. 431–45.

29

Max H. Bazerman, ‘‘Climate Change as a Predictable Surprise,’’ Harvard NOM Working Paper No.06-03 (June 7, 2005); available at ssrn.com/abstract=785990.

30

David Dembo, Ward Morehouse, and Lucinda Wykle, Abuse of Power—Social Performance of Multi-national Corporations: The Case of Union Carbide (New York: New Horizon Press, 1990), pp. 89–90.See also Dan Kurzman, A Killing Wind: Inside Union Carbide and the Bhopal Catastrophe (New York:McGraw-Hill, 1987).

31

For a review of authors using this argument, see Sandin, et al., ‘‘Five Charges Against the Precau-tionary Principle,’’ pp. 295–96; see also Julian Morris, ed., Rethinking Risk and the Precautionary Princi-ple (Oxford: Butterworth-Heinemann, 2000).

32

Kerstin Dressel, ‘‘The Cultural Politics of Science and Decision-Making: An Anglo-German Compar-ison of Risk Political Cultures—The BSE Case’’ (doctoral thesis, 2000); available at bse.airtime.co.uk/dressel.htm (last accessed July 31, 2006).

33

Discussed in Wybe Th. Douma, The Precautionary Principle: Its Application in International, Europeanand Dutch Law (doctoral thesis, 2002, unpublished), p. 230; compare EU Committee of the AmericanChamber of Commerce in Belgium, Position Paper on a Comprehensive Risk Analysis Process(September 9, 1999).

34

Quoted in David B. Resnik, ‘‘Is the Precautionary Principle Unscientific?’’ Studies in History and Phi-losophy of Science Part C 34, no. 2 (2003), pp. 329–44.

35

Henry Miller, ‘‘Letter to the Editor: The Bogus Precautionary Principle,’’ Wall Street Journal, March 1,2001, p. A23, quoted in Resnik, ‘‘Is the Precautionary Principle Unscientific?’’

36

Resnik, ‘‘Is the Precautionary Principle Unscientific?’’; Kenneth R. Foster, Paolo Vecchia, and MichaelRepacholi, ‘‘Science and the Precautionary Principle,’’ Science 288, no. 5468 (May 12, 2000), pp. 979–81;and Sandin, et al., ‘‘Five Charges Against the Precautionary Principle,’’ pp. 295–96.

37

Resnik, ‘‘Is the Precautionary Principle Unscientific?’’ p. 337.38

For a discussion of the use of animal bioassay in risk assessment, see Alan Rosenthal, George M. Gray,and John D. Graham, ‘‘Legislating Acceptable Cancer Risk from Exposure to Toxic Chemicals,’’ Ecol-ogy Law Quarterly 19, no. 2 (1992), pp. 269–362.

39

John D. Graham, Laura Green, Marc Roberts, ‘‘In Search of Safety: Chemicals and Cancer Risk,’’ as re-printed in Richard L. Revesz, Foundations of Environmental Law and Policy (New York: FoundationPress, 1997). As a default position based primarily on policy considerations, the EPA requires the useof linearized multistage (LMS) models. Justice Stephen Breyer has criticized this model as being a ‘‘tooconservative’’ method of estimating low-dose risks. By contrast, Adam Finkel has argued that this is ascientifically valid method (possibly superior to the threshold theories privileged by Breyer) that hasno conservative bias; Stephen Breyer, Breaking the Vicious Circle: Toward Effective Risk Regulation(Cambridge, Mass.: Harvard University Press, 1993); Adam Finkel, ‘‘A Second Opinion on an Environ-mental Misdiagnosis: The Risky Prescriptions of Breaking the Vicious Circle,’’ New York UniversityEnvironmental Law Journal 3, no. 2 (1994), pp. 295–381, available at www.law.nyu.edu/journals/envtl-law/issues/vol3/2/3nyuelj295.html; and Sheila Jasanoff, ‘‘Acceptable Evidence in a Pluralistic Society,’’in Deborah G. Mayo and Rachelle D. Hollander, eds., Acceptable Evidence: Science and Value in RiskManagement (New York: Oxford University Press, 1991), pp. 29–47.

40

Pat Kane, ‘‘There’s Method in the Magic,’’ in Jane Franklin, ed., The Politics of Risk Society(Cambridge, England: Polity Press, 1998), p. 77.

41

Sunstein, Laws of Fear, p. 35.42

Sunstein, Laws of Fear; and Breyer, Breaking the Vicious Circle.


43

Daniel Kahneman, Paul Slovic, and Amos Tversky, eds., Judgment Under Uncertainty: Heuristics andBiases (Cambridge, England: Cambridge University Press, 1982); Cass R. Sunstein, ‘‘Hazardous Heu-ristics,’’ University of Chicago Law & Economics, Olin Working Paper No. 165, and University of Chi-cago Public Law Research Paper No. 33 (October 2002); available at ssrn.com/abstract=344620; andCass R. Sunstein, ‘‘Probability Neglect: Emotions, Worst Cases, and Law,’’ Yale Law Journal 112 (Oc-tober 2002), pp. 61–107.

44

Paul Slovic, ‘‘Perception of Risk,’’ Science 236 (April 1987), pp. 280–85; Paul Slovic, ‘‘Beyond Numbers:A Broader Perspective on Risk Perception and Risk Communication,’’ in Mayo and Hollander, eds.,Acceptable Evidence, pp. 48–65. For an overview of the literature, see Bernd Rohrmann and OrtwinRenn, ‘‘Risk Perception Research—An Introduction,’’ in Ortwin Renn and Bernd Rohrmann, eds.,Cross-Cultural Risk Perception: A Survey of Empirical Studies (Dordrecth, Holland: Kluwer AcademicPublisher, 2000), pp. 11–54.

45

Slovic, ‘‘Beyond Numbers,’’ p. 65.46

For a seminal work in this area, see Mary Douglas and Aaron Wildavsky, Risk and Culture: An Essayon the Selection of Technical and Environmental Dangers (Berkeley, Calif.: University of CaliforniaPress, 1982); for an overview of theories, see Dan M. Kahan, Paul Slovic, Donald Braman, and JohnGastil, ‘‘Fear of Democracy: A Cultural Evaluation of Sunstein on Risk,’’ Harvard Law Review 119

(2006), pp. 1071–1109.47

Kahan, et al., ‘‘Fear of Democracy,’’ p. 1091.48

Ibid., pp. 1072–73.49

Ortwin Renn, ‘‘Concepts of Risk: A Classification,’’ in Sheldon Krimsky and Dominic Golding, eds.,Social Theories of Risk (Westport, Conn.: Praeger, 1992), p. 77.


reconstructing precaution, deconstructing misconceptions

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