The Light Was Green, According to Everyone
At 1812 you respond to a two-vehicle crash at the intersection of 5th and Harrison. Vehicle A was northbound; Vehicle B was eastbound. A’s front bumper struck B’s driver-side door. A says, “I had the green; B ran the red.” B says, “A ran the red; I had the green.” A bystander says A “entered on the yellow, maybe just after.” The signal has a 4-second yellow and a 2-second all-red. A’s skid marks measure 42 feet; B’s measure 18 feet. The road is dry. A’s driver is 19 with a provisional license; B’s driver is 47 and says he was doing “about 40” in a 45. A says the crash happened at 1805; B says 1808; the witness says “just after 6.” You have no video. Both vehicles are drivable.
1. Build a timeline using the stated times and identify which account is least consistent with the physical evidence and the bystander’s statement. Explain your reasoning without claiming to know the exact speed.
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Timeline: A claims 1805; B claims 1808; the witness says “just after 6”; the call is logged at 1812. The 1805 claim places the crash seven minutes before the call, the 1808 claim four minutes before, and the witness is too vague to resolve the minute. The call time does not prove either driver’s time, but it makes the 1805 claim less precise and worth testing.
The least consistent statement is A’s claim of a green light, because the bystander says A entered on yellow. Under standard phasing, a yellow for northbound A normally corresponds to red for eastbound B, but that must be verified against the actual signal plan. If the bystander is correct, A’s “green” claim is contradicted, and B’s “green” claim is also difficult to reconcile with a yellow for A. So the better conclusion is not “B is truthful” but “both drivers’ light-color claims are party statements that the independent witness partly contradicts.”
The skid marks do not prove speed. A’s 42 feet versus B’s 18 feet may reflect different speeds, different reaction times, different braking, or different vehicle weights. The length difference is a reason to investigate, not a finding of fault.
2. Explain how the damage pattern and skid-mark lengths should shape your interviews and scene documentation. What specific measurements or questions should you add?
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The damage pattern-A’s front bumper into B’s driver-side door-places B in A’s forward path at impact. That does not by itself establish who had the right-of-way, but it tells you what to document: the point of impact, debris field, gouge marks, tire marks, vehicle final positions, and distances from the stop bars and crosswalks.
The skid lengths should be measured from the start of the visible mark to the tire’s final position, with photographs and a notation of the road surface. Record whether the marks are skid, scrub, or ABS-related, and note tire condition. Do not convert length to speed without the proper formula, drag factor, and training.
Add these questions: Where was each vehicle when the driver first saw the other? What color was the signal when the driver entered the intersection? Did the driver brake before or after impact? What was the driver’s speed at entry? For the witness: where was the witness standing, what was the line of sight, and how long after the crash did the witness speak to anyone? Also request the signal timing plan and maintenance records for the intersection.
3. Write two neutral questions you would ask each driver to test their account without revealing what the other driver said.
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Ask both drivers the same open questions, separately:
- “Tell me what you saw of the traffic signal from the time you approached the intersection until you entered it.”
- “Where was your vehicle when you first noticed the other vehicle, and what did you do next?”
These are neutral because they do not mention red, green, yellow, speed, or the other driver’s version. They invite a narrative rather than a yes/no defense. Follow-ups should also be neutral: “What did you see the other vehicle doing?” and “What did you hear, if anything?” Avoid “Did you run the red?” or “The other driver says you were speeding-what do you say?” Those questions reveal the other account and invite the driver to tailor the story. If a driver changes the account, document the change and the exact words rather than arguing.