6.4 Accident Investigation & STARS Reporting

Crash Scenes: Safety First, Then Truth-Finding

Quick Answer: At a Missouri traffic crash, protect the scene and render aid / request EMS before turning the event into pure paperwork. Investigate with measurements, photos, and witness statements. Complete S.T.A.R.S. and other required reports when thresholds and location rules apply—remember that STARS is not required on all private-property accidents.

Crash investigation sits at the intersection of emergency medical response, traffic law, criminal law (hit-and-run, vehicular assault themes), civil liability, and statewide data systems. MPOLE tests priorities and reporting concepts as much as diagramming skill.

Scene Safety and Medical Aid Priority

Order of work

1. Arrive safely — Do not create a second crash. Approach with warning lights as policy dictates; park to shield the scene when practicable without blocking critical EMS access.
2. Hazard control — Fuel leaks, downed lines, fire, hazardous materials, airbag residual risk, unstable vehicles, traffic flow.
3. Life safety — Check for injuries; request EMS early; provide first aid within training and equipment.
4. Stabilization — Additional units for traffic control; fire for extrication/hazards; supervisors for major incidents.
5. Investigation and reporting — After immediate threats are managed.

Exam-aligned priority statement: At an injury accident, the officer priority is to secure the scene, render aid, and request EMS. Writing the report and chasing every fleeing witness come after life safety—though a hit-and-run flight may require simultaneous broadcast while medical aid is arranged.

Emotional and environmental control

Crashes produce anger, shock, and language barriers. Separate drivers when safe, speak calmly, and avoid premature fault declarations at roadside. Weather, darkness, and multi-lane interstate environments (I-44, I-70, I-270) increase secondary-crash risk—shorten on-scene exposure when possible using quick clearance principles consistent with evidence needs.

Evidence at Crash Scenes: Measurements, Photos, Witnesses

Good reports rest on observations, not guesses.

Physical evidence themes

• Final rest positions of vehicles and bodies (when applicable)
• Tire marks — skid, yaw, scrub; direction and length
• Debris fields and fluid trails
• Damage profiles — contact damage vs. induced damage
• Road evidence — gouges, paint transfer, pole/guardrail impacts
• Environmental factors — grade, sight distance, signals, weather, lighting
• Vehicle factors — brake condition observations, tire condition, lighting function post-crash when safe
• Human factors — impairment clues, restraint use, distraction evidence, statements

Measurements and diagrams

Use a consistent reference point (RP). Measure distances to wheels, marks, and objects. Note whether positions were as found or vehicles were moved for medical access (and by whom). A simple, scaled diagram with north arrow outperforms a paragraph of vague “near the intersection” language.

Photographs

Photograph overall approaches from drivers’ viewpoints, vehicle damage close-ups with identifiers, marks before they are driven over, traffic control devices, and any impairment or crime evidence. Digital photos are worthless without linkage in the report (who took them, when, what they show).

Witness statements

• Identify drivers, passengers, and independent witnesses early.
• Separate parties before statements when feasible.
• Capture contact information and direction of travel narratives.
• Record admissions carefully and note demeanor.
• For serious injury/fatality, treat as major investigation—preserve for reconstruction and potential criminal charges.

Missouri S.T.A.R.S. Accident Reporting

S.T.A.R.S. (Statewide Traffic Accident Reporting System) is Missouri’s framework for standardized crash data used by law enforcement and highway safety analysis. Officers complete the required crash report forms/processes for qualifying crashes so statewide statistics and local records remain accurate.

Critical official sample fact

MPOLE-style official sample material includes a true/false-style proposition:

“STARS must be completed on all private property accidents.” → False.

Not every crash on private property (parking lot, private drive) automatically requires a full STARS report. Reporting duties depend on statutory thresholds, injury, location, hit-and-run, and agency policy. Do not memorize the opposite extreme either—some private-property crashes do require reporting (for example, injury crashes or other criteria under current rules). The tested point is that “all private property accidents” is too broad.

Data quality

STARS data feeds engineering and enforcement planning. Incomplete contributing circumstances, wrong locations, or missing unit information degrade the system. Complete required fields carefully; use standard codes taught in training.

When Full Crash Reports Are Required vs. Minor Incidents

Exact dollar thresholds and form versions change; know the decision framework:

Generally expect full investigative reporting when

• There is injury or fatality
• There is significant property damage meeting the current reporting threshold
• Hit-and-run with investigative leads or serious damage/injury
• Commercial vehicles, hazmat, school buses, or other special categories per policy/statute
• Impairment, reckless conduct, or other criminal offenses are involved
• Public roadway crashes meeting state reporting criteria

Minor property-damage incidents

For low-damage, no-injury exchanges on some private property or under thresholds, drivers may be directed to exchange information and use civil processes, with officers providing assistance, a local incident card, or a short report as policy allows. Still:

• Check for injuries even when parties say they are “fine.”
• Watch for DUI cues.
• Ensure a safe traffic condition before clearing.
• Follow agency rules—never invent a “no report needed” rule that contradicts statute or policy.

Property-damage-only awareness: Drivers generally must stop, exchange information, and file/report when damage exceeds applicable thresholds. Leaving without fulfilling duties can become hit-and-run even without injury.

Hit-and-Run Investigation Basics

Leaving the scene of a crash can be a serious criminal offense. When injury is involved, Missouri practice materials treat leaving as a felony-level exposure with potential imprisonment—far beyond a “ticket.”

Immediate actions

1. Life safety for remaining victims; EMS.
2. Broadcast suspect vehicle description, direction of travel, damage pattern, plate if known.
3. Preserve scene evidence (paint transfer, debris from suspect vehicle, video canvass).
4. Interview remaining drivers, passengers, and witnesses; canvass businesses for cameras.
5. Document victim vehicle damage and scene as carefully as a “both parties present” crash—sometimes more so.
6. Follow-up — hospital interviews, repair shops, plate returns, social media tips per policy, detective referral for serious cases.

Common errors

• Clearing the scene without photographing perishable marks because “the other car left.”
• Failing to broadcast promptly.
• Accepting “I didn’t think I hit anything” without examining damage consistency.
• Ignoring impairment evidence on the remaining driver.
• Forgetting that private-property hit-and-runs can still be crimes even when STARS rules differ.

Missouri crash checklist for MPOLE

1. Is everyone safe? Is EMS en route or on scene?
2. Are secondary crashes prevented?
3. What physical evidence will disappear first?
4. Does this crash require a full report / STARS entry under location and severity rules?
5. If private property, am I incorrectly assuming “always STARS” or “never STARS”?
6. If hit-and-run, have I broadcast, preserved evidence, and started follow-up?

Crash work is where professionalism is highly visible. Prioritize life, preserve truth, and report accurately—including the tested STARS private-property rule: not all private-property accidents require STARS completion.