FMCSA Violations That Cause Truck Crashes

Commercial trucking runs under a federal safety code — the Federal Motor Carrier Safety Regulations — and when a crash traces back to a broken rule, the injury claim changes character. Instead of arguing about what a "reasonable" driver would have done, the case points at a specific regulation, a specific violation, and the records that prove it. This page covers the five rule sets most often behind serious crashes, each cited to its part of Title 49 of the Code of Federal Regulations, and explains — in plain English — the legal doctrine that makes violations so powerful.

Hours of service — 49 CFR Part 395

The fatigue rules. Property-carrying drivers may drive at most 11 hours after 10 consecutive hours off duty, all within a 14-hour on-duty window; a 30-minute break is required after 8 cumulative hours of driving; and weekly caps (60 hours in 7 days, or 70 in 8) limit total on-duty time. Since the ELD mandate, driving time is logged automatically from the engine — which turned fatigue cases from credibility contests into data reviews. Common violations: driving past the limits, editing logs, "personal conveyance" abuse, and carriers assigning schedules that only work if the driver cheats. The rules have legitimate flexibility — sleeper-berth splits, a 34-hour "restart" of the weekly clock, an adverse-driving-conditions extension — and defense teams lean on those provisions, which is exactly why the raw ELD data matters more than anyone's characterization of it. See the fatigue crash page for how these cases are built.

Inspection, repair & maintenance — 49 CFR Part 396

Carriers must systematically inspect, repair, and maintain every vehicle they control (§ 396.3); drivers must complete pre-trip inspections and written post-trip reports of defects (§ 396.11); defects that affect safety must be repaired before the truck runs again; and every vehicle needs a periodic (at least annual) inspection (§ 396.17). Brake-out-of-adjustment and tire violations are perennially among the most common roadside out-of-service findings nationwide. When a blowout, brake failure, or collapsed underride guard causes a crash, Part 396 records — or the absence of them — often decide the case.

Drug & alcohol testing — 49 CFR Part 382

CDL drivers are subject to pre-employment, random, reasonable-suspicion, and post-accident testing (§ 382.303 requires testing after fatal crashes and after injury/tow-away crashes with a citation). Carriers must also query the FMCSA Drug & Alcohol Clearinghouse before hiring and annually, so "we didn't know about the driver's history" rarely survives scrutiny. A missed post-accident test is itself evidence — juries are allowed to wonder why it didn't happen.

Cargo securement — 49 CFR Part 393 (Subpart I)

The securement rules prescribe minimum numbers and strength of tie-downs, blocking and bracing standards, and commodity-specific requirements for loads like coils, lumber, and vehicles. Part 393 also sets the equipment standards — brakes, lighting, and the rear impact guards whose failure defines underride cases. Lost-load crashes are usually Part 393 cases, and the liable party is often whoever loaded the trailer, not just whoever drove it.

CDL standards — 49 CFR Part 383

Part 383 sets who may hold a commercial license, the endorsements needed for tankers, hazmat, and doubles, and the disqualification rules for serious traffic offenses. Its companion, Part 391, makes carriers verify driver qualifications — application, license history, road test, medical certification — and keep a driver qualification file. A carrier that put an unqualified, disqualified, or medically uncertified driver behind the wheel faces negligent-hiring exposure layered on top of the crash itself. (Hazmat operations add Part 397's routing and attendance rules — see the hazmat page.)

Hazmat operations — 49 CFR Part 397

Carriers hauling placarded hazardous materials answer to an extra rule set: Part 397 restricts routing (avoiding populated areas where practicable, following state-designated hazmat routes), requires attendance of vehicles carrying certain classes, and controls parking near flames and buildings. Combined with the tank-endorsement and training requirements, hazmat cases give attorneys several additional regulatory hooks — and violations carry outsized jury weight because the potential harm is so obvious. See the hazmat and tanker page for the crash dynamics.

How violations get proven

Violation evidence comes from three directions. The truck's own records: ELD data, inspection reports, and maintenance files obtained through preservation demands and discovery — the primary source, and the perishable one. The government's records: every roadside inspection generates a report; the FMCSA's public SMS/SAFER data shows the carrier's violation history by category; and post-crash compliance reviews sometimes document systemic failures in the carrier's own words. Cross-checking: fuel receipts, toll transponder records, GPS pings, and delivery timestamps that contradict the official logs — the classic way falsified hours come apart. An experienced truck attorney runs all three tracks at once, which is another reason the first weeks of a case matter so much.

What a violation does not do

Honesty requires the other half: a violation is powerful evidence, not an automatic win. The violation still has to have caused the crash — a logbook error by a driver who was stopped at a red light when you rear-ended him proves little. Comparative-fault rules still apply, states differ on how much weight negligence per se carries, and carriers defend these cases hard. What a documented violation reliably does is shift leverage: it survives summary judgment, it reads clearly to juries, and it raises the settlement calculus — sometimes into punitive territory when the record shows the company knew.

"Negligence per se" — why a violation changes the case

Ordinarily, an injury claim must convince a jury the defendant failed to act with reasonable care. But in many states, when a defendant violates a safety law designed to protect people like the plaintiff from exactly this kind of harm, the violation itself can establish the breach — a doctrine called negligence per se. In plain English: the argument shifts from "the driver should have been more careful" to "federal law said 11 hours; the ELD shows 14." States differ on how the doctrine applies (some treat a violation as conclusive, others as evidence the jury weighs), but either way, a documented FMCSA violation gives a claim a spine it wouldn't otherwise have.

Where violations show up

All of these records age out or get overwritten on schedules described in our evidence guide — ELD data has a six-month retention floor, ECM data can vanish in days. Finding the violation requires having the records; having the records requires moving fast.

Was a rule broken in your crash?

You usually can't tell from the outside — the proof sits in the carrier's files, and it ages out on the retention schedules described above. A free case review puts an attorney who works with these regulations on the question within days rather than months, at no cost and with no obligation. Two minutes of questions below is all it takes to start.