A tractor-trailer hit your car, and now the trucking company's people seem to be moving faster than you are. That is not your imagination. A truck crash leaves behind more evidence than almost any other accident, and much of it sits in the hands of the company that has the most to lose.
The short answer
Commercial trucks record speed, braking, location, and driving hours, and carriers must keep logs under federal safety rules. Some of that data can be overwritten or thrown away in weeks or months if no one demands that it be saved. The single most important early step is a written preservation letter to the carrier, sent fast. After that, the case often involves more than one responsible company, and California's two-year deadline to file an injury lawsuit, under Code of Civil Procedure 335.1, still applies.
What evidence does a truck carry that a car does not?
A modern big rig is a rolling data recorder. Depending on the truck and the company, the evidence can include:
- Engine control module data, often called the black box: speed, throttle, brake use, cruise control, and sudden stops in the moments before a crash.
- Electronic logging device (ELD) records: the driver's hours on duty and behind the wheel, tied to the truck's engine and location.
- GPS and fleet tracking: where the truck was, how fast it went, and how long it stopped.
- Dashcams: many fleets run forward and driver-facing cameras.
- Dispatch messages and delivery schedules: what the company asked the driver to do and how tight the timeline was.
- Maintenance and inspection records: brakes, tires, lights, and the driver's own pre-trip inspection reports.
- Driver qualification file: license, medical certificate, training, prior violations, and the company's hiring checks.
- Post-crash drug and alcohol test results, which federal rules require after many serious crashes.
None of this shows up in a police report. You have to ask for it.
Why do hours of service and driver logs matter so much?
Federal Motor Carrier Safety Administration (FMCSA) rules limit how long a commercial driver can drive. For most interstate property carriers, a driver can drive up to 11 hours after 10 hours off duty, cannot drive past the 14th hour on duty, and must take a 30-minute break after 8 hours of driving. California has its own similar rules for trucks that never leave the state.
The ELD shows whether the driver was over the limit. Dispatch records can show whether the company pushed a schedule that only worked if the driver broke the rules. When those line up, the case is no longer about one bad moment on the freeway. It is about how the company runs its trucks.
How fast can truck evidence disappear?
Faster than most people expect. Federal rules require carriers to keep driver logs and supporting documents for six months. Dashcam footage on some systems loops and records over itself in days. Black box data can be lost when the truck is repaired, put back into service, or sold. Some carriers keep more than the minimum. Some do not.
If a key record is gone by the time anyone asks, it is very hard to prove what it would have shown.
What is a preservation letter, and why send it right away?
A preservation letter, sometimes called a spoliation letter, is a written demand to the trucking company, and often its insurer, to keep every piece of evidence connected to the crash. A good one names the truck, the driver, and each category of evidence, and asks that the truck not be repaired or sold until its data is downloaded.
Once the company is on notice, destroying that evidence carries real consequences. A California jury can be told that it may infer the missing evidence would have hurt the company that got rid of it. That possibility gives carriers a strong reason to keep what you asked for.
This is one of the first things we do when you hire us. If you were hit by a commercial truck, it is worth a free case review before the trucking company's records clock runs out.
Who can be responsible in a California truck accident?
In a car crash there is usually one driver and one insurance company. A truck crash can involve several parties, each with its own insurance:
- The driver, for speeding, distraction, fatigue, or an unsafe lane change.
- The motor carrier, the company operating the truck, for the driver's conduct on the job, for hiring or training failures, and for maintenance.
- The trailer owner or leasing company, if equipment failed.
- The shipper or loader, if cargo was overloaded or badly secured and shifted.
- The freight broker, in some cases, for choosing a carrier with a poor safety record.
- A maintenance shop or parts maker, if a brake job or a tire caused the failure.
- A public agency, if a city, county, or Caltrans vehicle was involved or a dangerous road design played a part. Those claims have a much shorter clock, explained in our guide to the six-month government claim deadline.
Interstate carriers hauling general freight must carry at least $750,000 in liability coverage under federal rules. Finding every responsible company and every policy is part of the work.
Where do truck crashes happen most in California?
Anywhere freight moves: the port corridors around Los Angeles and Long Beach on Interstate 710, the warehouse belt along Interstate 10 and Interstate 15 in the Inland Empire, and Highway 99 and Interstate 5 through the Central Valley. Each setting adds its own evidence, like port gate logs and warehouse yard cameras, which are also erased on a schedule.
What should you do after a truck accident?
- Get medical care and keep every record and bill.
- Photograph the truck, the trailer, the company name, and the USDOT number painted on the cab door.
- Get the driver's name and the carrier's name, and the names and numbers of any witnesses.
- Do not give a recorded statement to the trucking company's insurer. Our guide to recorded statements explains why.
- Do not sign anything or accept a quick check.
- Get a preservation letter out as soon as possible.
If the carrier says you were partly at fault, that does not end your claim. California's comparative fault rule reduces recovery by your share; it does not erase it.
Our truck accident lawyers handle these cases across California, and there is no fee unless we win. Call (310) 746-5775 or request a free case review today.
This guide is general information, not legal advice. Deadlines and rules change; talk to a lawyer about your situation.