police body worn camera videos as a collision reconstruction tool

“Body Worn Camera Videos

as a Reconstruction Tool”

A Practical Guide for the Investigation

and Reconstruction of Collisions using

Body Worn Camera Footage

Bobby J. Mullinax Senior Patrol Officer

Spartanburg Police Department

ABOUT THE PRESENTER

Bobby J. Mullinax began his law enforcement career in 2007 with the Spartanburg Police Department.

Prior to law enforcement, he worked in the collision refinishing and repair field with training and

experience dealing with both structurally and non-structurally damaged vehicles. He is currently pursuing

additional education in the field of automotive repair to better identify and address mechanical

malfunctions in collision vehicles.

In his law enforcement career he has investigated nearly 1,500 traffic collisions with an estimated 300

collisions involving minor or serious injuries including 8 fatal collisions where he was assigned in a lead

investigator role. He specializes in time and distance examinations working to identify under which

conditions a collision could have been avoided or the severity reduced. As a member of the Spartanburg

Police Department's Major Accident Investigation Team he reconstructed a fatal pedestrian crash in 2015

using only a body worn camera video, becoming one of the first collision investigators in South Carolina

to reconstruct a crash scene using only the emerging body cam technology. He has assisted in forensic

mapping of multiple crash scenes as well as serious crime scenes including murder.

He has received advanced training in collision reconstruction including the TCI Series, (At-Scene, Technical,

Reconstruction) TCI- Motorcycle Collision Investigation, TCI- Pedestrian/Bicycle Collision Investigation,

and Occupant Kinematics (IPTM). He has experience with animations and scale diagram drawings with

the Visual Statement EdgeFX program. He has attended numerous collision reconstruction conferences

and currently presents information on the usage of body worn camera videos as a reconstruction tool.

Bobby J. Mullinax

Senior Patrol Officer

Spartanburg Police Department

[email protected]

Work: (864) 591-4354

Bobby J. Mullinax began his law enforcement career in 2007 with the Spartanburg Police Department.Prior to law enforcement, he worked in the collision refinishing and repair field with training and experience dealing with both structurally and non-structurally damaged vehicles. He is currentlypursuing education in the field of automotive repair to better identify and address mechanical malfunctions in collision vehicles.

In his law enforcement career he has investigated nearly 1,500 collisions with an estimated 300 involvingserious of fatal injuries. He specializes in time and distance examinations working to identify underwhich conditions a collision could have been avoided or the severity reduced. As a member of the Spartanburg Police Department's Major Accident Investigation Team he reconstructed a fatal pedestriancollision in 2015, using only a body worn camera video, becoming one of the first collision investigatorsin South Carolina to reconstruct a crash scene using only the emerging body cam technology. He has assisted in forensic mapping of multiple crash and crime scenes. He has also assisted other collisionreconstructionists in the field with research projects, including deceleration testing of all terrain vehiclesat the 2015 SCARS conference in Mount Pleasant, S.C.

He has received advanced training in collision reconstruction, including the TCI Series, (At-Scene, Technical, Reconstruction), TCI- Motorcycle Reconstruction, TCI- Pedestrian/Bicycle Reconstruction,and Occupant Kinematics at IPTM in Jacksonville, F.L. In addition to formal training he has conductedextensive self study in may different areas of collision reconstruction including human factors andperception response times. He is familiar with several forensic mapping software programs and hascompleted multiple 3-D animations using the Visual Statement EdgeFx program. Please do not hesitateto consult Senior Patrol Officer Mullinax with any questions you may have in regards to using theinformation contained within this guide on your collision scenes.

Bobby J. MullinaxSenior Patrol OfficerSpartanburg Police DepartmentSpartanburg, South [email protected](864) 838-1729

OVERVIEW

Across the world the usage of body worn cameras by law enforcement agencies is on the rise, particularly in the United States. Currently 31 states have pending body camera legislation, which could have already increased by the time of this writing. In June of 2015, South Carolina Governor Nikki Haley signed in to law the first statewide body cam law directing every police department in the state to implement its usage. In that particular state, body cam videos would not be subject to Freedom of Information requests, but would be available to criminal defendants and civil litigants.

In a 2013 sampling of law enforcement agencies conducted by the Police Executive Research Forum (PERF) only 25% of responding agencies indicated they currently used body worn cameras. By 2015 a FOX6 news report estimated that the current body worn camera usage had increased to 1 in 3, or 33%.

The United States saw a 31% increase over a 13 year period in the usage of dash cam video technology. From 2000-2005 the usage of dash cams increased at an average of 3.6% per year. From 2013 to 2015 body worn camera usage increased from 25 to 33% which was an 8% increase over a 2 year period, or an average of 4% per year. If the usage of body worn cameras increases near the same rate, the percentage of police department in the United States using the technology could be close to 45 % by 2018. That’s if pending legislation in many states doesn’t influence the rate of increase.

In Canada the body worn camera is growing in usage. Many Canadian agencies have already been using BWCs on a trial basis. The Calgary Police Service began testing body cameras in 2012 and have set 2017 as a date to have all officers outfitted with the technology. The Toronto Police Service is currently in a testing phase for body worn cameras which will conclude in May 2016 at which time they will decide whether or not to adopt the technology. Police

services in Winnipeg and Montreal have also announced plans to experiment with the usage of body worn cameras.

37%

55%61%

68%

2000 2005 2007 2013

INCREASE IN DASH CAM USAGE BY LOCAL POLICE DEPARTMENTS- Bureau of Justice Statistics

Body cam usage is also on the rise across Europe, although many European agencies have been using body cams long before it was the popular thing to do. Danish Police are credited for adopting the first body worn cameras and in 2005 the first testing of body worn cameras began taking place by the Devon and Cornwall police in the United Kingdom. By 2007 the Home Office in the United Kingdom began encouraging the usage of body worn cameras and published the “Guidance for the Police Use of Body Worn Cameras”. By 2010 over 40 United Kingdom police areas were using body cameras. The Madrid Police Force is Span as well as the Mechelen police in Belgium have also began testing the usefulness of body worn cameras. These are

just a few examples with many other areas already testing, using, or in the planning phases for a body worn camera program.

Different countries, states, territories, etc. have different laws or policies governing what should and should not be recorded by body cam. Some agencies may elect to have officers record the duration of their entire shift while other agencies may only have officers record the time they are on a call. As the usage of body worn cameras increase across the globe these devices will have an unintended but highly positive effect on collision investigation and reconstruction.

INVESTIGATIVE USES

As the availability of body cam videos increases as their usage becomes more common place in law

enforcement the benefits to collision investigation and reconstruction will continue to increase. These

videos will help with reconstruction efforts to piece back together un-marked or partially marked scenes

which in the past have been believed to have been gone forever. Footage from crash scenes depicting

the collision site and vehicles involved will become invaluable in criminal and civil prosecution efforts.

Scene Depiction

The left screen shot is a still frame from a body worn

camera video that was recorded by an officer doing

a walkthrough of a collision scene. In the still frame

emergency responders are helping a small child

which was struck along with a second pedestrian by

a vehicle. The child, who appeared to be severely

injured on scene, made a full recovery after being

struck by the vehicle with the second pedestrian only

receiving minor injuries. The driver of the vehicle

was charged with the collision and received only

minor traffic related charges as well as facing civil

action from the pedestrians. The complete video

depicts the chaotic collision scene which you expect to see with a collision involving a small child. As a

law enforcement officer prosecuting felonious charges (Felony DUI, Reckless Homicide, etc.) or a private

consultant working on a major civil case, imagine the impact this collision scene video would have on

members of a jury, who have likely never witnessed a scene such as this.

Driver and Witness Interview

While old fashioned written statements are great tools for gathering a person’s recollection of events for

court purposes, that’s about all you get, their written recollection of events. Black ink on white paper.

Witness interview forms are great tools but are just two dimensional. By bringing body cam technology

in to your collision scene interviews the statements taken in conjunction with body cam video have more

of an impact than that of a plain written or audio statement. With on scene video you can feel as well as

hear what the witness is saying as the viewer can tap in to their full range of emotions. Also, the videos

of driver interviews conducted as part of the initial collision investigation, can have benefits later on that

would not have been expected. The still frame shot right is of an at fault driver in a fatal collision. The

driver initially told the officer he ran the red

light which was noted in the collision incident

report. The driver was sued in civil court and

during litigation the driver claimed he had

blacked out and was not driving negligently.

After reviewing body cam footage from the

collision investigation the driver would go on to

give the officer specific details of the collision,

such as seeing the car begin to pull out in the

roadway and then striking the vehicle in the

driver’s door. All of these details would have

been unknown to him had he actually blacked

out. Without this body cam footage the

blackout claim likely could have altered the outcome of the civil case, however after the footage was

reviewed the suit was settled out of court for $350,000 (USD).

Damage Documentation

In most areas a collision report will include some type of documentation as to where the damage on a

vehicle is located and the extent of that damage. Even with that in place, questions frequently arise after

the fact regarding vehicle damages. Was it existing prior to the collision? Was it caused during the

collision? Has the vehicle been damaged after the collision? By conducting a walk around visual inspection

using body cam video this footage can assist in answering these questions later on, without any added

steps in to the collision investigation process. During the investigation of one particular minor collision

an officer walked around the at fault vehicle involved in the collision. During the initial investigation the

driver made no claims about a third vehicle being involved. As the collision process progressed through

the insurance and civil phases, the at fault driver began to make claims that he was rear ended by a third

vehicle which caused him to strike the vehicle in front of him. The driver met with the original

investigating officer wanting the collision report amended to show a hit and run driver at fault and showed

the officer damage to the rear end of his vehicle allegedly caused by the hit and run driver. A review of

the body cam walk around of the vehicle on the original collision date showed no damage on the rear end

of the vehicle and disproved this claim of a third vehicle involved.

VEHICLE DAMAGE PROFILES

While the degree of difficulty is varying in each collision an investigator will face it is still possible to

complete a vehicle damage profile using body cam footage. While the body cam video will not be a

replacement for properly photographed and measured vehicles in the case of a vehicle which may have

been repaired or crushed since the original collision, the body cam footage is better than no evidence at

all.

Cadillac SRX

In this example the collision vehicle has stuck a pedestrian. This is the same vehicle involved in the case

study example of this guide. The Cadillac SRX was inspected, measured, and photographed and those

measurements were used as a baseline comparison.

Viewing the on scene body cam footage from the responding officer two areas of damage were located.

A dented portion on the hood, as well as a cracked portion of the front grille.

During the original reconstruction the original collision vehicle was used to obtain damage measurements.

For the purposes of this guide a like vehicle was located and the areas of damage were placed back on

this vehicle. This would simulate a vehicle that was repaired before inspection or a vehicle that’s owners

are not making easily available to the investigation. Using the style lines in the hood as well as the vents

in the grille itself the approximate measurements of damage

RECONSTRUCTION USES

While the usage of body worn camera footage will be beneficial in all areas of collision investigation and

reconstruction, the footage proves invaluable in the reconstruction of collision scenes which were not

properly photographed or documented. This lack or documentation could occur for a variety of reasons.

Many times a person’s internal injuries won’t display the full magnitude of their severity and the extent

of the injury is not known until after the time frame of the initial collision investigation has passed. Other

times a lack of training or inexperience in the on scene officer could play a part in evidence not being

properly photographed or marked. The collision scene may have been compromised by witnesses,

bystanders attempting to be good Samaritans, or fire or medical personnel before locations of all evidence

could be photographed or marked. Regardless of how you came to attempt to reconstruct a collision

scene based off body cam footage, establishing reference points can take you from no evidence to a full

reconstruction of the crash.

There are two main types of reference points used to place evidence back on the roadway in their original

location: roadway reference points and off roadway reference points. By establishing reference points

we can get the locations of evidence very near their original spots. This system of coordinating evidence

by usage of body worn camera footage can be used in small and large crash scenes. The larger the scene

the more the need for reference points grow. For example, in a large collision scene, the investigator may

use several different areas of reference points to locate particular items of evidence or to get in the

general area of evidence and then use additional reference points to narrow the area.

ROADWAY REFERENCE POINTS:

Roadway reference points will generally be used to place items or evidence back on the roadway itself.

The points can also be used to assist the investigator in locating a particular area of the roadway to look

for evidence points.

Roadway Markings

Pavement markings will be some of the most easily identifiable roadway reference points. They can range

from solid roadway lines, dashed roadway lines, turning arrows, words, etc. Dashed roadway lines can be

particularly helpful as the actual lines can be measured to help approximate distances in body cam still

frame shots. For example, if you were working a bicyclist crash in the top left photo, and the cyclist came

to rest between the dashed yellow lines and appeared to be halfway between the lines on the photo, the

actual lines could be measured and a mark made at the halfway point to represent to final rest of the

cyclist.

Roadway Reflectors

Roadway reflectors can be used to establish reference points on the roadway. They can also be used to

locate a particular area of roadway. Even if the collision you were reconstructing was an older case and

the reflector had been damaged or was missing, generally the patch of tar used to cement the reflector

to the roadway would still be visible. In the photo above, the right side depicts what an investigator would

expect to see when encountering a missing reflector. These can also be used for a reference point in the

event the reflector was already missing at the time of the collision.

Utilities

Covers for sewer access points as well as covers for water and gas shutoffs are commonly located within

the confines of the roadway.

Potholes

Potholes or evidence of repaired pot holes are commonly seen in the roadway. Like with road reflectors

if a pot hole is observed in the body cam footage of an older case there will be evidence in the roadway

of repair.

Roadway Damage

Areas of roadway damage could include gouges, scrapes, stress cracks in the roadway, or other defects

which could be identifiable.

Roadway Construction Transitions

Areas of the roadway in which their construction type transitions can be used to obtain reference points.

These type of transitions could include a general change in the construction type, ie asphalt to concrete,

or just an area of roadway which was repaved, ie light to dark asphalt. A transition to brick paver type

construction is also popular in crosswalk areas, or the entire roadway in cities.

OFF ROADWAY REFERENCE POINTS

Off roadway reference points are just as the name implies, reference points that will be found off the

roadway itself. ORRP are mainly used to place back evidence that is located off the roadway, or to get the

investigator to a general area of the roadway to look for additional reference points. In some cases an

ORRP may be used to locate items of evidentiary value which were located in the roadway itself.

Sidewalks and Curbing

Sidewalks and curing generally line most city streets and major roadways which may experience heavy

pedestrian traffic. This makes these items readily available to be used by the investigator in establishing

reference points. Particularly helpful to the investigator are contraction joints (cracks) found in sidewalks

and curbing. For example, if an investigator establishes the area where recording began and the

responding officer passes three contraction joints, or cracks, in the sidewalk as he passes by, the

investigator can use the same lines in the sidewalk to retrace the officer’s steps leading to the evidence.

Guardrails

Guardrails are a good source for reference points. Most guardrails will typically be bolted together in

multiple sections. Other reflective properties are usually placed on guardrails for night and low level

conditions. All of these items can be used to help lead the investigator back to evidence.

Cable Barrier

Cable barrier is a cost effective means to divide most interstate highway systems. Like guardrails they are

usually bolted together in sections with reflective properties added.

Concrete Medians

Concrete medians can also be found dividing interstate and major highways. Like sidewalks and curbing

the investigator can look for any discolorations or irregularities that stand out, and also use contraction

joints.

Trees and Other Landscaping

Trees and other landscaping items can be found along the roadway to assist the investigator with

reference points for evidence.

Fencing

Fences can be particularly helpful to the investigator. Like guardrails and barriers, fencing will be

constructed in sections offering many options for reference points. Barb wire fencing is also popular in

many rural areas where the roadway may not have many options, such as sidewalks, pavement markings,

etc. for obtaining reference points.

Utility Poles

Utility poles line the sides of roadways are can be used for obtaining reference points. Many utility poles

will have some type of marking on them which could be visible on the body cam footage at the right angle.

Also, these poles could be counted to help an investigator retrace the steps of the original responding

officer.

Signage

Signs such as Stop, Yield, Speed Limit, business signs, etc. can be used for obtaining reference points.

Signage can be easier to locate for the investigator trying to recreate a collision scene.

Utilities

Like with utilities on the roadway, utilities such as water and gas shutoffs, drainage, and phone line boxes

can be located for obtaining off roadway reference points.

Ground Transitions

Like with roadway construction type transitions, ground transitions such as grass to dirt, dirt to gravel,

grass to overgrowth, etc. can be used to obtain reference points.

Pavement Markings

Utility companies routinely make markings on the pavement along the roadway. Many times there will

be pavement markings in the collision scene which were not necessarily made by investigating law

enforcement officers. These marking can be used for reference points for your evidence.

While this is not an exhaustive list of reference points that can be found on or off the roadway, it

gives you a good starting point and some ideas on how to obtain your own reference points. These are

some of the most common found points but anything that you can locate in body cam footage that can

be located back at the collision site can be used. While recreating a collision scene from body cam footage

can be an arduous task, its importance is paramount to the people directly affected by the collision which

you are investigating. While the task becomes more difficult when scenes are not properly preserved if

you have a body cam footage of the incident you can find something to go on.

Even on this undivided two lane highway in the middle of nowhere there are multiple reference points

we could use to place back evidence in its proper location at the time of the original collision.

Some of the reference points observed are:

- Jagged roadway stress crack that resembles line from a heart monitor

- Large “H” shaped crack in roadway

- (2) Off Roadway ground transitions

- Open area of no vegetation off roadway

- Large roadway cracks that come together to resemble the letter “Z”

To put how obtaining reference points translates in to placing evidence back on the roadway

several examples have been added of real life collisions. All the following collisions are taken from the

field and show how to use body cam footage to reestablish your collision scene. All these collision scenes

were recreated using still frame photos from the body cam video or the footage itself. The choice of using

still frame photographs or video will be at the preference of the individual investigator. Once these scenes

were recreated they then could have been forensically mapped, speed estimates obtained, or any number

of other investigative processes.

Motorcycle vs. Toyota 4-Runner

In this example a motorcycle was heading north on a South Carolina primary highway when a Toyota 4-

Runner traveling south attempted a left turn in front of the rider. The SUV and motorcycle then collided

within the intersection. The motorcycle left pre-impact skids leading up to the area of impact.

The rear bumper of the SUV was seemingly in line with a large pavement crack. The pavement crack had

a second pavement crack that ran parallel to it several feet away. These parallel pavement cracks could

be used to place the rear left wheel back on the pavement. The end of the pavement crack could be

located and the rear left tire mark made 41.34 inches (105 cm) away from the end of the stress crack. This

is the distance of the rear overhang of the SUV which was obtained from vehicle specs. From there the

mark for the front left tire could made 105.51 inches (267.99 cm) from the rear left mark to account for

the SUV’s wheelbase. The tires could be oriented using the top pavement stress crack as the SUV seemed

to follow the same general line as the end of the stress cracks. The front right and front left marks could

then be made using the wheel track measurements.

After the general area of final rest for the 4-Runner is located the general area of the right front tire mark

could be searched for the stress cracks that seem to make a large “X” shape. This crack would give up the

location of the end of the motorcycle at final rest. The motorcycle specifications could then be used to

help locate the right rear tire, kickstand area where the skid ends, and the front tire area.

While the beginning of the skid tends to blend in with cracks in the roadway on this photo, it is apparent

to being a skid in the actual body cam video. Using the white stop bar the general area where the skid

begins can be located. From there additional body cam footage can show the impending skid portion

and reference points can be located to make the skid locations more precise.

Chevrolet Impala vs. Chevrolet Cruze vs. Honda Accord

In the following example a Chevrolet Impala was traveling east on the main roadway when a Honda Accord

approached a stop sign at an intersection with the main road. The Honda attempted to travel north across

the main roadway disregarded the stop sign striking the Chevrolet Impala. The Impala then traveled in to

the west bound lanes of travel striking a Chevrolet Cruze.

The raised concrete median area was used to place the Impala back on the roadway in the west bound

lanes of travel. The back right wheel of the Impala was positioned at the upper right corner of the median.

Also the front right tire which came off during the collision was located in the upper left corner of the

median.

The upper left area shows the points which were marked to indicate where the Impala and the front right

tire came to rest. The markings have been circled to assist the viewer in locating them in the photo. Once

the back right wheel point was located the wheel track and wheel base measurements of the vehicle were

used to assist with obtaining additional markings. The body cam photo was used to help orient the angle

of the vehicle at final rest.

Final Rest Cruze

The Chevrolet Cruze was placed back on the roadway by using the yellow square of raised dots. The

contraction joint in the curbing was used to assist in obtaining the angle of the Cruze at final rest.

As with the Impala once the first mark was obtained for the left front wheel of the Cruze the wheel base

and wheel track measurements were used to aid in locating the additional tire locations.

Final Rest Honda

The Honda came to rest in the middle of the intersection with no readily available reference points

observed on the body cam footage. Instead of writing the Honda off as a loss reference points from

further back were used to help orient the Honda back on the roadway. The front wheels of the Honda

seemingly line up with the while line which separates traffic in the east bound lanes. The front of the

Honda also lined up with the area between the fourth and fifth dashed white lane from the curb at the

intersection. The Honda was then placed back on the roadway in the area where these lines connected.

In the above left photo the intersecting area of the roadway where the middle of the Honda’s front end

was observed is located. Once the mid-point of the vehicle was located it was marked. Once that point

was located the track width was adjusted and used to locate the front wheels. Then the Honda’s

wheelbase was used to locate the rear wheels of the Honda.

Chevy Silverado vs. Pontiac Bonneville

In this example a Silverado was traveling east on the main roadway on wet roadways during the beginning

stages of snowfall. While driving east the Silverado began to slide at which time the truck crossed a small

brick and landscaped type barrier before traveling in to the west bound lanes clipping a Pontiac traveling

west. The truck then slid to final rest along the curb line as the Pontiac went in to a slide striking a utility

pole along the sidewalk area.

The original collision report has the collision occurring near the entrance/exit of an apartment complex.

This area is out of view of the still frame photo in the above left but is visible on camera. The general area

of the final rest of the Silverado is two dashed white lines from the entrance/exit of the complex. The top

right shows the area at the second dashed stripe showing the Silverado’s position relative to the end of

the stripe.

The above left and right photos show the angle or orientation of the Silverado on the roadway. As

observed in the top left the tire of the Silverado is completely against the curb while the rear left tire is

slightly away from the curve. To better place the rear left tire back on the roadway it is slightly visible that

the tire itself is still partially on the concrete area of the roadway and not completely on the asphalt

section.

The above photo shows the points once they were located and the tire locations of the Silverado placed

back on the roadway. Once the front left tire location was found the wheelbase and wheel track

measurements were used to assist in locating the additional tire locations while using reference points to

aid in the vehicle’s orientation.

The area in which the truck crossed over the median was also located. In the above left you can see the

area the truck first began crossing over has caused damage to shrubbery. This damage is just beyond a

road reflector in the east bound lanes. To pinpoint the location where the tires began coming back on to

the roadway in the west bound lanes the area between the second and third dashed white lanes were

used. Once getting in this general area a road reflector on the west bound side of the median was or a

reference point.

The top left photo shows the mark which was made for the tires beginning to go off road while the top

right shows the approximate area the Silverado began to travel in to the west bound lanes of travel. This

would be the line for the longer mark observed in the body cam still frames. To obtain the shorter mark

a tape measure could easily be used to establish the visible line and additional points or markings could

have been made to show the shorter drag mark.

While as much video footage of the final rest of the Pontiac was not made enough footage exists for us

to place the vehicle back at its final rest location. The above photo shows the Pontiac at rest against the

utility pole at the area of the passenger side view mirror.

The correct utility pole as observed on body cam footage was located using the silver cylinder attached

to the pole as well as using road lines to help establish its general area. From there the approximate

distance from the mirror to front right wheel hub was used to place the tire back on the sidewalk.

Above right the marking is visible after being established.

Roll Over Example

In this example a Ford Explorer attempts to “beat” the traffic light and turn off the main road and on to

a secondary highway. The traffic signals changes for cars traveling east and west on the main road and

they proceed forward. While attempting to clear the intersection the Explorer is struck in the rear right

area causing the Explorer to begin skidding sideways before overturning. The Explorer makes one

complete roll and comes to rest back on its wheels. For the purpose of this example the final rest of the

van was not used as the driver moved the van from the main roadway before police arrival.

The rear end of the Explorer was stopped near the entrance/exit to a business. As the officer walked

past the Explorer he passes three sidewalk contraction joints before arriving near the front of the

vehicle. The front end of the Explorer is closely in line with the third sidewalk contraction joint. This is

also the area where the smooth transition in to the parking lot ends and the curbing along the street

begins.

Once the contraction joint was located the front overhang measurement of the vehicle was used to

obtain the front right tire mark in relation to the contraction joint. The area of darkened roadway was

used to place the tire’s position in to the roadway itself. After the front right tire location was found the

wheelbase and wheel track measurements were used to obtain the additional three tire locations.

The painted directional arrow, yellow center line, and road reflectors were used to place the drag marks

back on the roadway. This is the area the Explorer was sliding on metal as it right to right itself before

coming to rest.

The circled areas in the above left photo show where the markings for the beginning and end of the

scrape marks were made. The above right shows lines indicating their direction during the slide.

Finally the gouge mark where the Explorer first overturned was located. Although this collision was six

months old at the time of the photo in the above right the gouged area is still visible and the relocation

of the gouge with reference points is not needed. By comparing both side by side there are still many

areas that could be used for reference points if needed.

Is it possible to use a series of reference points obtained from body cam footage and place evidence back

on a roadway with any accuracy? This will have several mitigating factors including the skill level of the

investigator, the quality of body cam footage, the quantity of available reference points, and the overall

commitment of the investigator but it is possible to achieve very accurate results.

Validation Example # 1

In August 2015 an officer with the Spartanburg Police Department was involved in an on duty collision

with second privately owned vehicle. The officer was traveling east when the second vehicle disregarded

a stop sign at the intersection traveling south. The patrol vehicle and second vehicle then collided with

the patrol vehicle coming to rest partially in the roadway and partially on the sidewalk area. The other

vehicle struck a utility pole and then came to rest. The South Carolina Highway Patrol investigated the

collision and the Spartanburg Police Department’s Major Accident Investigation Team completed an in

house reconstruction of the collision. The collision scene was marked off by the SCHP and was later

forensically mapped by the SPD MAIT. As part of the MAIT investigation an officer conducted a

walkthrough of the collision scene while recording with his body camera.

The left side tires were placed back in their position at final rest by utilizing reference points obtained by

way of the section of raised crossing dots. The front left tire was near the top left corner of the crossing

dots, while the left rear tire was near the bottom right corner and the approximate width of the crossing

dot section in to the roadway.

Once the locations were found they were marked and measured for diagramming purposes. The same

was done for the location of the Nissan involved in the collision with the patrol vehicle.

When viewing the footage of the Nissan the left tire is approximately 1 foot in front of a water shut off

valve in the roadway. The car then seemingly lines up with the curb line leading up to the utility pole in

which it struck.

After the locations were measured two drawings of the scene were completed for comparison. One being

the drawing done with total station forensic mapping of the marked collision scene and the second from

the body cam footage locations.

In the above left photo the scene diagram completed of the marked collision scene is shown, while in the

above right photo the scene diagram of the body cam collision scene is shown. The measurements

obtained of the reference points were imported in to the drawing from the original collision scene.

Once all the body cam measurements were imported both final rests from both drawings were overlapped

to see how close the body cam reference point vehicles were to the marked collision scene vehicles. In

the above photo the marked vehicles are in red while the body cam vehicles are the ghost white outline.

The center mass locations of the reference point vehicles were within 6-7 inches on both vehicles from

their original locations.

Validation Example # 2

In February 2016 officers from the Spartanburg Police Department’s traffic division responded to a vehicle

versus pedestrian collision. An officer activated a body worn camera upon his arrival to document the

scene and location of the pedestrian. The collision scene was marked and photographed as part of the

collision investigation. The body worn camera footage was then viewed for the purpose of obtaining

reference points. In the below photos the left side is still frames taken from the body worn camera

footage while the right side are photos taken a few weeks after the collision investigation. The paint from

the original collision investigation is still visible on the roadway to show the close proximity to the actual

locations as the reference points located.

The officer activates his camera as exiting his patrol vehicle and as he walks on to the sidewalk area two

points are located to establish where the officer stepped on to the sidewalk at. In the above photo you

can see a point of a roadway irregularity and a transition from in sidewalk width. Once on the sidewalk

the officer walks passing a total of twelve sidewalk contraction joints (cracks) until arriving at the final rest

of the pedestrian.

While not totally visible in the above photo, it was determined that the area along the third contraction

joint that the officer walked past was the best established area of impact. The actual impact would have

taken place off camera from this particular still frame.

As the officer passes the seventh sidewalk contraction joint he arrives at the front of the striking vehicle.

In the above right photo the marking from the vehicle are visible and show their exact location in

comparison to the seventh contraction joint.

The officer then arrives at the final rest of the pedestrian at contraction joint number twelve. Again in the

above right photo the marked location of the pedestrian final rest is observed in relation to the

contraction joint.

As you can see in the above comparison photos had we used these contraction joints for reference points

our evidence locations would be very close to the locations of the actual collision. But what about

obtaining speed estimates from these markings?

Speed Estimate Comparisons

Throw Distance Ped Drag Factor Take-off Angle Searle

Marked Collision 44 ft (13.41 m) .80 10 degrees 28.99 mph (46.65 kmh)

Body Cam Points 44.41 ft(13.57 m) .80 10 degrees 29.13 mph (46.88 kmh)

Conclusion

While the practice of only viewing serious or fatal crash scenes should not replace proper documentation,

in the absence of scene markings the two validation examples show that it is possible to obtain results

extremely close to those of properly documented collision scenes by using the reference point method.

While the results will be limited to the individual investigator’s effort and abilities, with the right attitude

and willingness to put forth effort the finished result can take a case from nothing to a full blown

reconstruction.

On January 23, 2015 at 07:11 A.M. eastern standard time, officers with the Spartanburg Police Department responded to the report of a pedestrian vs. vehicle collision. Once on scene the responding officer determined that the injuries to the pedestrian did not appear to be life threatening. The pedestrian was conscious and alert and was transported to the hospital. Due to the belief that the injuries were not of a serious nature the collision scene was not photographed, documented, measured, marked off, or otherwise preserved. One week after the collision occurred the pedestrian died as a result of injuries that were sustained after being struck by the vehicle and falling the pavement.

After the pedestrian died from his injuries to collision was turned over to the department’s Major Accident Investigation Team and assigned to Senior Patrol Officer Bobby J. Mullinax for review. At the time the MAIT unit was assigned the investigation the only information available was the original South Carolina Traffic Collision Report filed by the original officer on scene and a copy of the body worn camera footage of the active collision scene. The original collision report noted that the pedestrian was the contributing party and was walking west across the roadway in to the path of the striking vehicle. The body worn camera footage was viewed several times and then the video was broken down using reference points to place the evidence back on the roadway.

To establish the final rest of the pedestrian the body cam video was viewed for the purpose of locating roadway or off roadway reference points. When viewing video footage two reference points were located to assist officers in locating the general area of pedestrian final rest. One was the road reflector located next to the double yellow stripe. The second reference point located was an off color section of concrete curbing.

To place the striking vehicle back in the area of its final rest, again two roadway reference points were established. The first reference point was again the roadway reflector located next to the double yellow roadway stripe. The second reference point was a large crack in the asphalt construction of the roadway. The crack ran through the painted yellow line making it an easily visible reference point. To distinguish this crack from the other roadway cracks, the first reference point of the road reflector was largely used to establish the general area of the roadway crack reference point. In the above body cam still frame the responding officer has paused to return his pen to his shirt pocket while standing in front of the striking vehicle. Had there been an absence of a second reference point near the front of the striking vehicle, the officer’s width could have been used to obtain the distance between the roadway reflector and the front of the striking vehicle. Additionally, while it is not necessary for completing a speed range estimate, for diagramming purposes these reference points could be used to place back the scattered cigarettes and the bag which the pedestrian was carrying.

After the striking vehicle was placed back on the roadway as close to its original final rest position as possible, additional footage from the body cam was used to orient the position of the vehicle at final rest. This was done for diagramming purposes as the angle of the vehicle did not affect its travel distance. As noted in the above photo the striking vehicle came to rest completely in the opposing lanes of travel. The vehicle was oriented in the roadway by placing the edge of the right front tire on the left double yellow line and the edge of the right rear tire on the outside of the right double yellow line. Once the reference points were established from the body cam footage the collision scene was examined to locate the established reference points.

After the reference points were located the areas of final rest for both the pedestrian and the striking vehicle were marked. These marks would later be used to establish the distances under which the collision occurred. After marking the roadway the vehicle involved in the collision was inspected and a formal statement was obtained from the driver.

The driver stated they did not see the pedestrian until impact took place and then they immediately braked. The driver also stated that pedestrian was not within the crosswalk area of the intersection. No claims by the driver of the pedestrian being within the intersection itself were made. An inspection of the pedestrian and the vehicle revealed bruising on the right side of the pedestrian at the same height as the bumper of the striking vehicle indicating no braking prior to impact. Using the driver’s statement the MAIT unit determined that the striking vehicle most likely slowed to begin left turning movements before remaining at a constant speed while completing their turn on to the roadway. This was also in line with a naturalistic traffic survey of drivers making the same turning movements as the collision driver. Using the measurements obtained from the roadway the MAIT unit then began to use time and distance and establish a range of speeds under which the collision could have occurred. For the purposes of establishing a speed range other examinations and driver studies were conducted at the intersection and impact speeds under 10 mph (16 km/h) were ruled out.

SPEED STOPPING DISTANCE PRD @ 1.5 SECONDS RESPONSE AND STOP

10 MPH (16 km/h) 8.33 FEET (2.53 m) 21.99 FEET (6.70 m) 30.32 FEET (9.24 m)


12 MPH (19 km/h) 12 FEET (3.65 m) 26.38 FEET (8.04 m) 38.38 FEET (11.69 m)

13 MPH (20 km/h) 14.08 FEET (4.29 m) 28.58 FEET (8.71 m) 42.66 FEET (13 m)





18 MPH (28 km/h) 27 FEET (8.22 m) 39.58 FEET (12.06 m) 66.58 FEET (20.29 m)



From the top line of the crosswalk to the area of final rest of the vehicle there was a distance of 40.75 feet (12.42 m). This gave us the distance in which the collision had to occur. Based on the evidence of no braking and the driver’s statement that she did not see the pedestrian this distance must account for her reaction and vehicle response distance as well. Had this distance not been accounted for the speed estimates would have been higher than those the collision actually occurred under. In the above chart the speeds that the vehicle most likely had at impact was found to be 10-12 mph (16-19 km/h). These speeds also are under the speeds in which you would commonly begin to find bone fractures in the pedestrian, which were absent in this case. In the full reconstruction report a range of response times were used other than the 1.5 seconds used in the above chart. Under the above conditions the pedestrian would have been very likely to be within the crosswalk area at the time of impact. The crosswalk area was found to be the area within 30 – 40.75 feet (9.14 – 12.42 m) from final rest. As a result of this reconstruction the original collision report was amended to show the driver as the contributing party due to her turning movements being on the wrong side of the road. Additionally the direction the pedestrian was walking was changed to reflect his actual travel path. While the circumstances of this reconstruction were not the most ideal, this is an example of how body worn camera videos can be used to successfully complete an investigation with no other evidence available.

SPECIAL THANKS

A special thanks to those who assisted with this guide:

Sergeant Paul Roper, retired, Spartanburg Police Department

Spartanburg Police Department Traffic Division

police body worn camera videos as a collision reconstruction tool

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