Fatigue, Impairment & Dangerous Behavior

Driver-related factors are present in roughly one-third of all fatal large truck crashes. These factors fall into three categories: fatigue caused by hours-of-service pressure and undiagnosed conditions, impairment from drugs or alcohol, and dangerous behaviors like distraction and speeding.

Key Findings
  • 160K+

    Injuries from large truck crashes annually

    NHTSA FARS 2022
  • 28%

    Inspected trucks had brake violations

    CVSA Roadcheck 2023
  • 23×

    Higher crash risk when texting at the wheel

    FMCSA Research
  • 153K+

    Drug & alcohol violations in Clearinghouse

    FMCSA Clearinghouse 2025

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Reference

Driver Error vs. Carrier Liability

Factor Driver Liable Carrier Liable Both Liable
Hours-of-service violation (isolated)
HOS violation with systemic carrier pressure
Drug use, unknown to carrier
Drug use, carrier ignored red flags
Distracted driving (personal phone use)
Speeding on tight carrier schedule
FAQ

Frequently Asked Questions

  • When a commercial-vehicle crash involves emergency braking, jackknife motion, trailer swing-out, loss of steering control, or departure from the roadway, ABS sensor integrity should be treated as a core vehicle-condition question. The relevant evidence includes the sensor, tone ring, wiring harness, connector condition, ECU diagnostic history, malfunction-lamp circuit, trailer-to-tractor communication path, maintenance records, and inspection history. The central question is not simply whether the truck had ABS installed, but whether the system had reliable wheel-speed data when it was needed.
  • Trailer ABS systems face harsher reliability conditions than tractor-mounted systems. Trailer wiring and sensor circuits are exposed to road spray, vibration, corrosion, loading cycles, suspension movement, and tractor-trailer articulation. Sensor harnesses may run near axle assemblies, suspension components, brake chambers, or frame rails. Over time, wiring can chafe, connectors can loosen, and moisture can enter electrical contacts. CVSA’s warning-lamp assessment found ABS malfunction conditions in approximately one in three trailers, compared with one in six power units.
  • CVSA inspection guidance summarized a warning-lamp assessment finding that approximately one in six power units and one in three trailers were operating with ABS malfunction conditions. During the 2023 International Roadcheck campaign, inspectors documented 4,127 ABS violations across power units, trailers, and motorcoaches. Brake systems remained the leading vehicle out-of-service violation category during the 2025 International Roadcheck, reinforcing that braking-system condition remains a persistent enforcement concern across the commercial-vehicle fleet.

  • ABS sensor failures can result from a damaged wheel-speed sensor, contaminated tone ring, corroded connector, chafed harness, missing communication circuit, or failed warning-lamp circuit. Wiring and sensor circuits are exposed to road spray, vibration, corrosion, loading cycles, suspension movement, and tractor-trailer articulation. Over time, wiring can chafe, connectors can loosen, and moisture can enter electrical contacts. When that happens, the vehicle may still have service braking force, but the anti-lock control function may be unavailable or unreliable.
Continue Exploring
  • Mechanical Failures

    Brake defects, tire blowouts, cargo securement, and maintenance failures that cause catastrophic crashes.

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  • Driver Error

    Fatigue, impairment, and dangerous on-road behavior—and the systemic pressures behind them.

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  • Crash Evidence

    The critical window for preserving physical and electronic evidence before it disappears.

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  • Company Liability

    How carrier hiring practices, training failures, and cost-cutting create conditions for preventable crashes.

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