Traffic Crash Investigations - Chapter 12

Traffic Crash Defined

• A traffic crash involves one or more vehicles in motion, resulting in property damage, personal injury, serious bodily injury, or death.
• Such crashes are generally unintentional and non-criminal.
• Intentional crashes are considered crimes like aggravated battery or murder.
• Every traffic crash should be treated as a potential crime scene until proven otherwise.

Florida Statute Chapter 316

• This chapter governs traffic crash investigations in Florida.

Ten Steps for Managing a Crash

• Approach the scene safely.
• Assess the scene.
• Secure the scene for safety.
• Provide first aid, if needed.
• Gather information related to the crash.
• Investigate the cause of the crash.
• Complete the Driver Exchange of Information.
• Take appropriate enforcement action.
• Return the scene to normal as quickly as possible.
• Document everything relating to the crash.

Approaching the Scene Safely

• Drive immediately and safely to the crash scene.
• Prioritize safety by following driving principles and using lights and sirens when necessary.
• Obtain as much information from dispatch as possible, including vehicle descriptions.

Assessing the Scene

• Your initial response should include a quick assessment to decide if you need to request additional assistance
• As you approach, be aware of any hazardous materials.
• Request additional resources such as EMS if required.
• Locate all involved vehicles and people.
• Identify all types of damage including skid marks, and damaged signs, landscaping and buildings.
• Manage fires, and downed powerlines.

Hazardous Materials

• Hazardous material (Hazmat) is any substance that, when released, may cause harm to humans, animals, or the environment.
• CBRNE threats include chemical, biological, radiological, nuclear, and explosive hazards.
• The Emergency Response Guidebook (ERG) identifies hazardous materials and outlines basic actions for first responders.
• The ERG has color-coded sections:
  • White: Introduction, instructions, guidance, and placards.
  • Yellow and Blue: Identify materials.
  • Orange: Response guidelines related to hazards, safety, and emergency response.
  • Green: Evacuation details.
• The U.S. Department of Transportation uses a four-digit numbering system (UN/NA) to identify hazardous materials.

Determining Jurisdiction

• The first harmful event is the initial event in a traffic crash that results in injury or property damage.
• Evidence of the first harmful event can include crash debris, fixed property damage, broken glass, and gouge marks.
• If the first harmful event occurs outside of your jurisdiction, protect the scene and wait for the correct agency to arrive.
• If the jurisdiction is unclear, contact Florida Highway Patrol.

Securing a Safe Environment

• The primary tool for controlling traffic is your vehicle.
• Position your vehicle to protect the scene, prevent secondary crashes, and redirect traffic flow.
• Turn on your vehicle’s emergency lights, but keep your headlights on low.
• Always remain visible while directing traffic.

Moving Crash Vehicles

• Move vehicles out of the roadway to prevent additional accidents, if the circumstances allow it
• Normal procedure requires moving vehicles as soon as possible unless:
  • There are injuries or fatalities.
  • Vehicles are too disabled to move.
  • The crash is a crime scene.

Positioning Warning Devices

• Warning devices include barricades, flares, message boards, signs, traffic cones, and reflective triangles.
• Consider the extent of the scene, the number of traffic lanes, and environmental conditions when positioning the warning devices.
• The final resting place is the point when all movement resulting from the crash comes to a halt.
• Create a roadblock if there is no safe way to protect the scene using traffic control devices.

Classifying Traffic Crash Injuries

• None: No injury.
• Possible Injury: Injury is reported or claimed.
• Non-incapacitating Injury: A non-disabling injury such as a laceration, scrape, or bruise.
• Incapacitating Injury: A serious bodily injury that prevents normal bodily functions.
• Fatal Injury: An injury resulting in death within a 30-day period after the traffic crash.
• Non-Traffic Fatal Injury: Fatality unrelated to the traffic crash, such as a heart attack or suicide

Information Gathering

• Obtain driver's licenses, vehicle registration, and proof of insurance.
• Confirm information using DAVID, FCIC/NCIC, and other databases.
• It is required to provide specific information at the scene of a crash.
• Passengers are not required to give a statement by law, only they do so voluntarily, unless the driver is unable to make their own statement.

Phases of a Traffic Crash

• Pre-Collision Phase:
  • Point of Perception: When the driver becomes aware of a danger.
  • Reaction Time: The time between perception and the start of evasive action.
  • Evasive Action: Any action taken to avoid a hazard.
  • Point of No Escape: The point when a crash is inevitable, regardless of any evasive actions.
• At-Collision Phase:
  • Encroachment: When vehicles begin to enter the same space at the same time.
  • Maximum Engagement: The point at which the vehicles crush together to the greatest extent.
• Post-Collision Phase (Disengagement): Begins when the vehicles separate.

Vehicle Dynamics

• Vehicle dynamics is the movement of vehicles during and after a collision.
• Area of Collision (AOC): The location of the first harmful event or damage in the crash.
• Point of Impact: The place where a vehicle or object struck another vehicle, object, or the road.

Types of Damage

• Preexisting Damage: Damage existing on a vehicle before the crash.
• Contact Damage: Damage that did not exist before the crash, resulting from direct pressure or impact.
• Induced Damage: Damage that did not exist before the crash but is not visually evident at the scene.

Types of Road Evidence.

• Gouge: A cut into the road surface caused by a vehicle part, indicating the AOC.
• Scrape: A broad area of scratches and streaks made by a sliding metal part.
• Runoff: A pool or trail of fluids escaping from a vehicle due to the impact.
• Debris: Loose material spread across the road due to the crash.

Tire Marks

• Skid Mark: Black mark left by a tire sliding while unable to rotate.
• Incipient Skid/Impending Skid Mark: Type of skid mark left by an ABS. The place where the skid mark begins to be measured. Temporary and may only be visible for 15-20 minutes.
• ABS Scuff Marks: Patterns left by a vehicle with ABS when a driver brakes hard. The tire mark from a wheel that is both rotating and slipping on the road surface.
• Intermittent Skid Marks: A series of skid marks with long gaps of more than 15 feet between them, caused by rapidly applying and releasing the brakes.
• Skip Skid Marks: Series of skid marks, usually short in length with irregular intervals between them. Cars that have a sudden load shift from breaking hard, or the vehicle is bouncing.
• Offset Skid Marks: Skid marks that indicate a sudden change in the direction of a tire due to collision forces.
• Squeegee Mark: Strip of dry pavement remaining after a vehicle skids on a wet road.
• Furrow Mark: Trench dug by locked tires moving across a soft surface, such as gravel, sand, grass, or dirt.
• Scuff or Yaw Mark: When a vehicle loses tire traction from entering a curve too fast or from over steering the tires. Tires continue rotating, but slide sideways, striping from the side motion of the tires.
• Acceleration Scuff Marks: Result from rapid acceleration like burnouts, gradually fading dark tire marks.
• Tire Print: Mark left by a tire rolling over a soft material or liquid.

Measuring Crash Scene

• Use rolling measuring wheels, fiberglass measuring tapes. and laser measuring devices.
• Measure temporary evidence first.
• Field Sketch: A rough drawing of the scene

Gathering Driver Information

• Per Florida law, drivers must exchange information, with the help of form HSMV 90011S if the officer does not use this form, then the officer must, at a minimum, provide each driver with the other parties driver and vehicle information.
• Officers have 10 days to submit an accident report

Traffic Violations

• Contributing Traffic Violations: Direct cause or contribution to the crash.
• Non-Contributing Traffic Violations: No direct bearing on the cause of the crash, but discovered during the investigation.
• Non-Traffic Violation: A criminal offense discovered during the crash investigation.

Returning the Scene to Normal

• If appropriate, remove hazards and debris from the road or request a tow company to do so.
• Per Florida Law drivers of operable crash vehicles should move their vehicles off the road.

Crash Documentation

• Florida traffic crash report forms and the manual are created and published by the dhsmv and available for use from from their website.
• The HSMV is the official record custodian for completed traffic crash reports.
• Two basic forms for traffic crashes:
  • HSMV 90011S: Driver Report of Traffic Crash/Self Report or Driver Exchange of Information.
  • HSMV 90010S: Traffic Crash Report (Long Form, Short Form, or Update Form).

Long vs Short Form

• Long form (HSMV 90010S):
  • A duty to investigate and submit when the crash results in a death, personal injury, the drive leaves the scene, if driving while under the influence, a vehicle was rendered inoperable, a commercial vehicle was involved
  • Includes an event section, a vehicle section, a person section, narrative section and a diagram section.
  • Recommending a driver for reexamination.
• Short form (HSMV 90010S):
  • Made up of an event section, vehicle section and a person section. No need for narrative.
• Update form (HSMV 90010S):
  • Includes a medical reporting form, to correct blood alcohol content or other corrections that occur. To update from previous report.

The Shift from civil to criminal

• Civil Traffic investigations are civil investigations at first because a driver has a statutory duty to report to the officer. But at some point, there will be a shift from civil to criminal. At this time, the driver needs to be informed that the investigation is shifting from civil to criminal. and any further information should not be taken from the civil investigation portion of the traffic investigation.
• Because during a civil traffic incident there is a Crash privilege that allows them to provide information about what happened without worrying that it will be used against them.
• When the investigation changes from civil to criminal their crash privilege ends This is known as changing hats If the driver is no longer free to leave because you're detaining them, you must read them their Miranda
  • In a hit and run crash, crash privileges do not apply to hit and run suspects

Other types of traffic crashes

• Traffic crashes involving unattended vehicles or property Notify the owner of the vehicle and the damage that was done.
• Single Vehicle crashes If one witness is present, make sure that the witness can establish that the person they witness is the same person, and that that person was the driver.
• Traffic crash involving a fatality or Serious bodily injury Per protocol the scene would be a crime scene and there all measurements should be taken.