Reviewed by Larry Forman, Attorney
In many serious crash cases, the two drivers' stories don't match, and there's no video. That's when accident reconstruction matters. A trained reconstructionist uses the physical evidence (skid marks, crush damage, where the vehicles came to rest, vehicle data) to work out speeds, positions and timing. Along with doctors and other qualified witnesses, reconstruction is how trial lawyers turn "he said, she said" into proof a jury can rely on.
What is accident reconstruction?
Accident reconstruction applies physics and engineering to a crash. A reconstructionist may answer questions like:
- How fast was each vehicle going at impact, and before braking?
- Where was each vehicle in the lane, and who crossed the line?
- Could the driver have seen the hazard and stopped in time?
- Was the light green, yellow or red when each car entered the intersection?
- How did the occupants move inside the vehicle?
Reconstructionists often come from law enforcement crash teams or engineering backgrounds. Police reports sometimes include a reconstruction for serious crashes, but in many cases no full reconstruction is done unless a lawyer arranges it.
What accident reconstruction uses
- Scene evidence: tire marks, gouges, debris fields, final resting positions, road grade and sight lines
- Vehicle damage: crush depth and direction, which help estimate impact speeds and angles
- Event data recorders: many passenger vehicles have one. Federal rules list the data a covered recorder must capture, including indicated vehicle speed, throttle and whether the brake was applied (49 CFR 563.7). Trucks carry their own engine and logging data; see truck black box evidence.
- Video: dashcams, business cameras and doorbell cameras, analyzed frame by frame
- Signal timing records for intersection crashes. See intersection crashes in Kentucky.
- Phone records, where distraction is an issue
- The police report and scene diagrams. Here's how to get your Kentucky accident report.
Much of this evidence is gone within days or weeks. Cars are repaired or scrapped, video is overwritten, and marks fade. See evidence to preserve after an accident.
Other opinion witnesses in injury cases
Reconstruction proves how a crash happened. Other qualified witnesses often explain what it did:
- Treating doctors explain the diagnosis, the treatment and whether an injury is permanent.
- Life care planners project future medical needs for serious injuries.
- Economists and vocational witnesses estimate lost earnings and lost earning capacity.
- Engineers may testify about a defective vehicle part, a road condition or a work-zone setup.
These witnesses often make the difference in what a case is worth. See what affects a Kentucky injury case's value.
Kentucky's rule for opinion testimony: KRE 702
A judge decides whether an opinion witness can testify. Since July 1, 2024, Kentucky Rule of Evidence 702 has required the side offering the testimony to show the court it is "more likely than not" that:
- The testimony "is based upon sufficient facts or data";
- The testimony "is the product of reliable principles and methods"; and
- The witness's opinion "reflects a reliable application of the principles and methods to the facts of the case."
That's the text of the Kentucky Supreme Court's order amending KRE 702, effective July 1, 2024. The witness must also be qualified by knowledge, skill, experience, training or education, and the opinion must help the jury understand the evidence or decide a fact.
In practice, this means a reconstruction has to be built on real measurements and accepted methods, not guesses. Defense lawyers challenge opinions that skip steps. Good reconstructions are built to survive that challenge.
When does a case need accident reconstruction?
Not every case does. A rear-end crash with clear fault and a police report often doesn't. Reconstructionists measure what happened against Kentucky traffic laws, such as speed and right-of-way rules. Reconstruction matters most when:
- Fault is disputed and there's no video
- Speed is the key question
- Several vehicles were involved, and the order of impacts matters
- A truck or commercial vehicle was involved. See our truck wreck page.
- Someone died and can't tell their side. See wrongful death.
- The insurer blames you, including for a share of the fault. See what to do if you were partly at fault.
How opinion witnesses fit into the lawsuit
Both sides usually disclose the opinion witnesses they plan to call at trial, and Kentucky's civil rules allow discovery of those witnesses' facts and opinions, often including a deposition. The defense will hire its own reconstructionist and doctors. Trials often turn on whose work holds up better under cross-examination.
That's why preparation matters. A reconstruction that's been tested against the defense's strongest arguments before trial puts real pressure on an insurer to settle, and holds up if it doesn't.
How Forman & Associates helps
We preserve the vehicles, data and video early, bring in reconstructionists and other qualified witnesses when a case needs them, and prepare every opinion to meet KRE 702 and hold up on cross-examination. When an insurer won't be fair, we're ready for court: Larry Forman has tried 50+ jury trials and won 95% of them. See our case results and our Louisville car accident practice.
Accident reconstruction FAQ
What does an accident reconstructionist do?
A reconstructionist uses scene evidence, vehicle damage, event data recorders and video to work out speeds, positions and timing in a crash. They can then explain those findings to a jury.
Can vehicle "black box" data show how fast a car was going?
Often, yes. Many passenger vehicles have event data recorders. Federal rules require covered recorders to capture data including indicated speed, throttle and braking. The data has to be preserved before the vehicle is repaired or scrapped.
What is the KRE 702 standard in Kentucky?
Since July 1, 2024, the side offering opinion testimony must show the judge it's more likely than not that the testimony rests on sufficient facts or data, uses reliable principles and methods, and applies them reliably to the case.
Does every car accident case need a reconstruction?
No. Clear-fault cases often don't. Reconstruction matters most when fault or speed is disputed, several vehicles were involved, a truck was involved, or someone was killed.
Does the police report count as a reconstruction?
Not usually. Police reports record what officers saw and were told. Some serious crashes get a full police reconstruction, but many don't.
Talk to a Louisville car accident lawyer
If fault in your crash is disputed, call Forman & Associates Accident Injury Lawyers at (502) 931-6788 or get a free case evaluation. Our office is at 1139 S. 4th St., Louisville, KY 40203. No fee unless we win.
This post is general information about Kentucky law, not legal advice. Reviewed October 2026.
