Why do we need good

forensic science ?

A Jamieson

The history of the justice systems The history of the justice systems of the world provide many examp of the world provide many examp

lesles of flawed decisions. of flawed decisions.

AA direct consequence of flawed e direct consequence of flawed e ye witness testimony ye witness testimony..

The scope for error in the The scope for error in the forensic processforensic process

The diligent, professional, dispassionat The diligent, professional, dispassionat e and impartial scientist e and impartial scientist..

will glean the maximum information fro will glean the maximum information fro m the most meagre physical evidence. m the most meagre physical evidence.

The unintentional may be caused by an The unintentional may be caused by an error anywhere in the chain of search, r error anywhere in the chain of search, r

ecovery, analysis, interpretation or rep ecovery, analysis, interpretation or reportort..

ExplanationExplanation WW ho is the target. ho is the target.

WW hat is the purpose of the explanation. hat is the purpose of the explanation.

Quality of EvidenceQuality of Evidence The quality of evidence must not The quality of evidence must not

be confused with the standard be confused with the standard of analytical accuracy and of analytical accuracy and precision.precision.

ScienceScience The scientific expert must be c The scientific expert must be c

onstantly cognisant of at least t onstantly cognisant of at least t he following facts he following facts..

firstly, never totally discount the firstly, never totally discount the possibility that the effect that youobserve possibility that the effect that youobserve could have occurred in a different way to could have occurred in a different way to what you surmise.what you surmise.

Secondly, know the limitations of the Secondly, know the limitations of the tests we use. Fewtests have no false tests we use. Fewtests have no false positives or false negatives.positives or false negatives.

Thirdly, know the difference betweenThirdly, know the difference between

experience and expertise.experience and expertise.

Experience and expertiseExperience and expertise

A scientific expert then requires spe A scientific expert then requires spe cial knowledge of science,not just a c cial knowledge of science,not just a c

asual awareness gained through expe asual awareness gained through experiencerience

- - What is science What is science

- W- W hat makes a conclusion hat makes a conclusion

- E- E xplanation scientific xplanation scientific

USA USA - Expert witness- Expert witness

1 The Frye Test --->> General 1 The Frye Test --->> General AcceptanceAcceptance

2 The Daubert Test 2 The Daubert Test

- Relevancy- Relevancy

- Reliability- Reliability

- Peer review- Peer review

- Known error rate- Known error rate

- Standard controlling- Standard controlling

- acceptance relevant community- acceptance relevant community

Thailand Thailand - Expert witness- Expert witness

The Criminal Procedure Code The Criminal Procedure Code Count 243 Count 243

LAW 0F EVIDENCE

1. Admission

2. Absolute or lrrebuttable Presumption

3 .Generally Known Fact

4. Evidence

Admissibility Of Evidence

1. Admissible Evidence

2. Inadmissible Evidence

the people whose lives will depend the people whose lives will depend upon the practitioner's capability to upon the practitioner's capability to report clearly and accurately the report clearly and accurately the results of their investigation. If results of their investigation. If forensic science is to achieve and forensic science is to achieve and maintain the status it deserves, maintain the status it deserves, each of us owes this duty of care to each of us owes this duty of care to all of those affected by our work.all of those affected by our work.

ConclusionConclusion

THANK YOUTHANK YOU