Rear-Ended: What to Do in the First 10 Minutes, and Why a Clean Bumper Proves Less Than You Think

This article is for general information only and is not legal advice.

The first ten minutes, in order

You were stopped, or nearly stopped, and something hit you from behind. The other driver is probably apologetic. Your neck may feel fine. The sequence below is built for exactly that moment, when everything still exists in one place and nobody has told the story to an adjuster yet.

1. Hazards on, then out of the lane if the car drives and it is safe. If you can take one photo of both cars where they stopped in under thirty seconds without stepping into traffic, take it. If you cannot, skip it. The position photo is useful; it is never worth standing in a live lane.
2. Check for injuries and call 911 if anyone is hurt or a car cannot move. Injury crashes have their own reporting duties, covered below.
3. Exchange the items the Vehicle Code lists, by photographing them. California requires drivers to exchange name, current residence address, driver license number, vehicle identification number, the registered owner's address, and evidence of financial responsibility, which for an insured driver means the insurer's name and address and the policy number, under Vehicle Code section 16025. A photo of the license and the insurance card captures all of it without a transcription error.
4. Photograph the damage the way an estimator will look at it. Your rear bumper straight on and from six feet at an angle, the other car's front, both plates, the trunk seam and whether it latches, the tow-hook cover, and any waviness in the bumper cover. The section on bumpers below explains why the angle shots matter.
5. Photograph the scene. The lane, the signal or sign, skid marks, debris, and the view from behind your car in the direction the other driver came from.
6. Witnesses before they leave. A name, a phone number, and one sentence of what they saw. A passenger in the other car is a witness too, though an interested one.
7. Describe, do not assign. "I was stopped at the red light and you hit me from behind" is a description. "It's fine, don't worry about it" is a statement you may hear quoted later. Say what happened and leave fault to the file.
8. Time and place. Your phone stamps both on every photo by default. Keep it that way.

The full at-scene list, for any crash, is in our car accident checklist. The general sequence after any crash is in what to do after a car accident. This article stays on what is specific to being hit from behind.

Why the rear driver is usually, but not automatically, at fault

The rule that puts the fault question on the following driver is short. Vehicle Code section 21703 says a driver "shall not follow another vehicle more closely than is reasonable and prudent, having due regard for the speed of such vehicle and the traffic upon, and the condition of, the roadway." That is the whole section. There is no number of seconds or car lengths in it; the three-second guidance you may have learned comes from driver training, not the statute.

Because keeping the distance is the following driver's duty, the rear driver usually carries the fault question in a rear-end crash. Usually is the operative word. California apportions fault between drivers, so a car that reversed at a light, brake lights that were not working, a lane change that cut the gap to nothing, or a third car that pushed the middle car forward can all shift part of the fault to someone else.

The things that would shift it are also the things that disappear first. Whether your brake lights worked is a photo you can take at the scene and cannot take a week later. Whether the light was red is on the signal timing, on a traffic camera if there is one, and in the memory of the witness who has not driven off yet. Whether there was a third car is obvious at the scene and invisible afterward. A police report records what the officer observed and what each driver said; our guide to reading a California police report covers what it does and does not decide.

"There's barely a scratch": what a bumper is built to hide

Federal law sets a performance standard for passenger car bumpers, and it is worth knowing what it protects. Under 49 CFR Part 581, a car must take a 2.5 mile per hour impact, and a 1.5 mile per hour impact at the corners, without damage to safety-related systems: the hood, trunk, and doors must still open and close, the fuel and cooling systems must not leak, the exhaust and propulsion, suspension, steering, and braking systems must work, and lamps must function. It is a functional standard. It does not say the bumper cover must look untouched, and it says nothing about what happens above the test speed.

A modern bumper is a painted plastic cover over an energy absorber over a steel or aluminum reinforcement bar. The cover flexes and springs back. The absorber and the bar behind it do not. That is why "barely a scratch" and a repair estimate that includes a reinforcement bar are both common after the same low-speed hit, and why the photos that matter are the ones that show what a flat, head-on snapshot hides: the cover at an angle for waviness, the gap between the cover and the trunk lid, the trunk seal, whether the trunk latches cleanly, and the tow-hook cover, which often pops when the absorber compresses.

Those photos are taken in two minutes at the scene. The estimate that relies on them may be written weeks later, by someone who never saw the car with the cover still warm.

The car was recording: what the event data recorder keeps

Most late-model passenger vehicles carry an event data recorder, and federal rules govern what one records when it is present. Under 49 CFR Part 563, a recording is triggered when the car's forward speed changes by 8 kilometers per hour, about 5 miles per hour, within 150 milliseconds. The elements the rule defines include vehicle speed, the change in velocity, whether the brake was applied, seat belt status, throttle position, and airbag timing, over the seconds before impact. The rule applies to vehicles that are equipped with a recorder; if yours has one, this is what it holds.

In a rear-end crash the recorder that matters most is in the striking car, because it holds the braking story: speed on approach, whether and when the brake was applied, and the moment of impact. Yours holds the mirror image, including whether you were moving.

Two things the recorder does not do. It does not upload anywhere on its own; the data stays in the vehicle and is read out with a tool, typically through the diagnostic port. And it is not permanent. Later events can overwrite it. That is a practical reason to document the crash as one that happened: the data exists at the scene, and whether anyone ever retrieves it depends on there being a record that it occurred.

Day one to day three: delayed symptoms and the paper trail

The neck injury most associated with rear-end crashes does not keep the crash's schedule. The NHS notes that "it can take several hours for the symptoms to start after you injure your neck." The Cleveland Clinic puts it more fully: some symptoms begin right away, others take at least 12 hours to appear, and sometimes it takes a full day or a few days for all of them to show up.

The practical consequence is a record-keeping one. Note the time anything starts, see a clinician if it does, and keep the visit record with the crash photos. "I felt fine at the scene" and "my neck started hurting the next morning" are not contradictions; they are the normal timeline, and a dated note of when the symptom began is the thing that connects the two. None of this is medical advice. If you are unsure, get checked.

What happens inside a claim file after it opens, and the clocks that regulate it, is the subject of our claim investigation timeline. This article stays at the scene and the days right after.

The deadlines that started at the light

The DMV report. If anyone was injured, however slightly, or anyone died, or any one person's property took more than $1,000 in damage, California requires an SR-1 report to the DMV within 10 days under Vehicle Code section 16000. The threshold is per person's property, not per crash, and a reinforcement bar alone can clear it. The duty applies whether or not police attended and whether or not the drivers made any arrangement between themselves.

The long clocks, for context only. California gives two years to bring an action for personal injury under Code of Civil Procedure section 335.1 and three years for damage to property under section 338. Those are not deadlines to plan around; they are the reason the record should outlive your memory of the afternoon. What to do when no officer comes at all is its own situation, covered in car accident with no police report.

"They want to keep insurance out of it"

It is a common offer after a low-speed rear-end hit, and it is often sincere. Two things from the sections above are worth holding next to it. Private arrangements tend to come apart when the cover comes off the bumper or when a symptom starts on day two, and at that point the record from the scene is all either driver has. And the SR-1 duty is keyed to injury and to the damage threshold, not to whether the drivers made a deal; a private arrangement does not switch it off.

Whatever you decide, record the offer as a fact: who offered what, when, and in what words, ideally in a text message you both have. Whether to accept a private arrangement is your decision and, where money or injury is involved, one to take with a licensed attorney in your state.

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