Speeding

The Most Documented and Most Preventable Cause of Truck Crash Fatalities

Speeding is not a gray area in commercial trucking. It is a measurable behavior, recorded second by second in the truck’s engine control module, verifiable against posted speed limits, and prohibited by federal regulation. When a commercial motor vehicle exceeds the speed limit, the margin between a recoverable situation and a fatal crash narrows with every additional mile per hour. Stopping distances increase exponentially. The energy that must be absorbed in a collision rises disproportionately to the speed increase. A 50 percent increase in impact speed produces a 125 percent increase in crash energy.¹ At those force levels, the structural protections built into passenger vehicles and the human body’s tolerance for deceleration are routinely overwhelmed.

In 2023, speeding contributed to 11,775 traffic fatalities nationwide, accounting for 29 percent of all traffic deaths for the year.² That figure includes all vehicle types, but commercial trucks are disproportionately represented in the most severe crashes because of the mass differential between a loaded tractor-trailer and the vehicles it strikes. When a truck traveling above the speed limit collides with a passenger car, the physics are unforgiving. The truck’s kinetic energy is a function of both its mass and the square of its velocity, and an 80,000-pound vehicle traveling 10 miles per hour over the limit carries substantially more destructive energy than the same vehicle at the posted speed. The occupants of the smaller vehicle absorb nearly all of that energy.

The regulatory framework treats speeding by commercial drivers as a serious matter with escalating consequences. Federal law classifies excessive speeding—defined as 15 mph or more above the posted limit—as a serious traffic violation that can result in disqualification from operating a commercial motor vehicle.³ And unlike many driver behaviors that must be proved through witness testimony or inference, speeding is recorded by the truck itself. The engine control module (ECM) captures vehicle speed at one-second intervals, creating an objective, timestamped record that either confirms or contradicts every claim about how fast the truck was traveling before a crash.

The Scale of the Problem

The relationship between speed and fatality risk is not linear. It is exponential. IIHS research has established that when impact speed increases from 40 to 60 mph—a 50 percent increase—the energy that must be managed in the crash increases by 125 percent.⁴ This means that relatively small increases in travel speed produce disproportionately large increases in crash severity. A truck traveling 10 mph over a 65 mph speed limit is not 15 percent more dangerous than one traveling at the limit. It is substantially more dangerous, because the additional speed translates into crash forces that exceed the design limits of the vehicles and restraint systems involved.

Rising Speed Limits and Rising Fatalities

The problem has intensified as speed limits have risen. Since the repeal of the national maximum speed limit in 1995, states have progressively increased their maximum posted limits. Currently, 22 states have maximum speed limits of 70 mph, 10 states allow 75 mph, and nine states permit 80 mph or higher on some portion of their road systems.⁵ Research has consistently shown that when speed limits are raised, actual travel speeds increase, and fatalities follow. IIHS research found that increases in speed limits over more than two decades were associated with approximately 37,000 additional deaths, with each 5 mph increase in the maximum state speed limit associated with an 8 percent increase in fatalities on interstates and freeways and a 3 percent increase on other roads.⁶ The effect is particularly pronounced for large trucks. Truck crash deaths on roads with speed limits of 75 mph or higher have increased sharply as more states have adopted these higher limits, reflecting the compounding effect of higher speeds on vehicles with longer stopping distances and greater mass.

Speeding Is Still the Second-Highest Factor in Fatal Crashes

The 2023 NHTSA data confirms the persistence of the problem. The 11,775 speeding-related fatalities represented a 3 percent decline from 12,157 in 2022, but speeding remained the second-largest contributing factor in fatal crashes after impaired driving.⁷ An estimated 332,598 people were injured in speeding-related crashes in 2023.⁸ The economic cost of speed-related crashes was estimated at approximately $46 billion annually.⁹

The Federal Regulatory Framework

Federal regulations address speeding by commercial motor vehicle drivers through several provisions that impose obligations on both the driver and the carrier.

Compliance with State Speed Laws (49 C.F.R. § 392.2)

Under 49 C.F.R. § 392.2, every commercial motor vehicle must be operated in accordance with the laws, ordinances, and regulations of the jurisdiction in which it is being operated, including speed limits.¹⁰ This regulation incorporates every state and local speed law by reference, making any speeding violation by a CMV driver simultaneously a violation of federal regulation.

Serious Traffic Violations and CDL Disqualification (49 C.F.R. § 383.51)

Under 49 C.F.R. § 383.51, excessive speeding is classified as a “serious traffic violation” for CDL holders. Speeding involving any speed of 15 mph or more above the posted speed limit triggers the serious traffic violation provisions.¹¹ A second conviction of any serious traffic violation within a three-year period results in a 60-day disqualification from operating a commercial motor vehicle. A third or subsequent conviction within three years results in a 120-day disqualification.¹² These disqualification periods apply whether the driver was operating a CMV or a personal vehicle at the time of the violation, provided the conviction results in suspension or revocation of the driver’s license.

Impaired Alertness and Operational Pressure (49 C.F.R. § 392.3)

Under 49 C.F.R. § 392.3, a motor carrier may not require or permit a driver to operate a commercial motor vehicle while the driver’s ability or alertness is impaired by any cause that makes it unsafe to drive.¹³ While this regulation is most commonly applied to fatigue, it also encompasses situations where a carrier’s delivery schedule or operational pressure creates conditions that incentivize speeding.

Carrier’s Duty to Require Compliance (49 C.F.R. §§ 390.11, 390.13)

The carrier’s obligations extend beyond the driver’s conduct. Under 49 C.F.R. § 390.11, whenever a duty or prohibition is imposed on a driver, the motor carrier has an independent duty to require observance of that duty or prohibition.¹⁴ A carrier that sets delivery schedules requiring average speeds that can only be achieved by exceeding posted limits, or that compensates drivers in ways that incentivize speed over compliance, has failed in this obligation. Under 49 C.F.R. § 390.13, no person may aid, abet, encourage, or require a motor carrier or its employees to violate the regulations.¹⁵

ECM Data Provides Definitive Evidence

The engine control module, or ECM, in a commercial truck records vehicle speed continuously, creating a second-by-second record of how fast the truck was traveling throughout its operation. This data is captured automatically, without the driver’s involvement, and is stored in the ECM’s memory. In the context of a speeding-related crash, the ECM data is among the most powerful categories of evidence available because it eliminates the ambiguity that characterizes other forms of speed evidence.

Witness estimates of vehicle speed are notoriously unreliable. Accident reconstruction calculations based on physical evidence—skid marks, crush damage, trajectory analysis—provide valuable information but involve assumptions and margins of error. The ECM record, by contrast, captures the actual speed of the vehicle at each second of the recorded interval. If the ECM shows the truck was traveling at 72 mph in a 55 mph zone for the 30 seconds preceding a hard-brake event, that data point is not an estimate. It is a measurement, recorded by the vehicle’s own electronic system, timestamped to the second.

Pre-Impact Behavior

The ECM data also reveals the driver’s behavior in the critical seconds before impact. Was the driver accelerating or decelerating? Was cruise control engaged, and if so, at what set speed? When was the brake first applied? How much speed did the truck lose between the first brake application and the moment of impact? Each of these data points speaks directly to the question of whether the driver was operating within the speed limit, whether the driver reacted to the developing hazard, and whether the truck’s speed at impact was survivable for the occupants of the other vehicle.

Telematics and Fleet-Wide Speed Monitoring

Telematics systems used by many carriers provide an additional layer of speed data. Fleet management platforms record GPS-derived speed at regular intervals, creating a continuous speed profile that can be mapped against posted speed limits along the truck’s route. A carrier that subscribes to a telematics platform has access to real-time and historical speed data for every truck in its fleet. If that data shows a pattern of chronic speeding by a particular driver, i.e., repeated instances of exceeding the limit by significant margins across multiple trips, and the carrier took no corrective action, the telematics record becomes evidence of the carrier’s knowledge of and tolerance for the driver’s speeding behavior.

Carrier Liability for Speeding-Involved Crashes

Speeding-related crashes create carrier liability through multiple pathways. The most direct is respondeat superior: the carrier is vicariously liable for the driver’s negligent operation of the truck within the course and scope of employment. A driver who was speeding at the time of a crash was violating both state speed laws and 49 C.F.R. § 392.2, and the carrier bears liability for that violation.

The carrier’s independent negligence may also be at issue. A carrier that knew or should have known that a driver was habitually speeding and took no corrective action may face a negligent retention claim.

The evidence supporting this claim comes from the carrier’s own systems:

• Telematics data showing repeated speed violations
• ECM downloads from prior trips
• CSA scores reflecting speeding-related inspection violations
• Internal disciplinary records (or the absence of any disciplinary response) documenting the carrier’s handling of the driver’s speed history

Operational Practices That Incentivize Speeding

The carrier’s operational practices may also contribute to the analysis.

• Dispatch records showing delivery windows that are mathematically incompatible with legal driving speeds and hours-of-service compliance suggest that the carrier created the conditions for speeding
• Compensation structures that pay by the load or the mile rather than by the hour create financial incentives for drivers to speed in order to maximize earnings
• Safety policies that prohibit speeding on paper but impose no consequences for violations documented by telematics demonstrate that the prohibition is not enforced

In jurisdictions that permit punitive damages for conduct reflecting conscious disregard for safety, a carrier that had telematics data showing a pattern of speeding, never addressed it with the driver, and continued to dispatch the driver on routes requiring highway travel faces exposure beyond compensatory damages. The ECM and telematics data establish the pattern. The absence of corrective action establishes the carrier’s indifference. The crash establishes the foreseeable consequence.

Evidence That Supports Speeding-Related Truck Crash Claims

Discovery in a speeding-related truck crash case should capture the full picture of the driver’s speed history and the carrier’s response to it.

Key categories include:

• The ECM download from the truck involved in the crash, covering the maximum available time window before and after the event
• All telematics and GPS speed data for the truck and driver for the 90 days preceding the crash, with posted speed limit data for the routes traveled
• The carrier’s CSA scores and roadside inspection history, with particular attention to speeding-related violations under the Unsafe Driving BASIC
• The driver’s motor vehicle record, including any speeding convictions
• All internal communications, disciplinary records, coaching logs, and safety meeting records related to the driver’s speed behavior
• The carrier’s dispatch records, delivery schedules, and on-time performance metrics for the trips assigned to the driver
• The carrier’s written speed policies, driver handbook provisions on speeding, and any progressive discipline procedures for speed violations
• Compensation records showing how the driver was paid (e.g., by the hour, by the mile, by the load, or by percentage) and whether the pay structure created incentives to speed

The objective is to establish not just that the driver was speeding at the time of the crash, but whether the speeding was an isolated event or part of a pattern that the carrier knew about, had the data to detect, and chose not to address.

Why Speed Matters More for Trucks

The consequences of speeding are amplified in commercial trucking by three physical realities that do not apply to passenger vehicles with equal force.

Stopping Distance

A fully loaded tractor-trailer traveling at 65 mph requires approximately 525 feet to come to a complete stop under ideal conditions, accounting for perception time, reaction time, and braking distance.¹⁶ At 75 mph, that distance increases substantially because braking distance is proportional to the square of the speed. The additional stopping distance means that a speeding truck needs more road to stop than the road may provide. A hazard that a truck traveling at the posted limit could have avoided becomes unavoidable at 10 mph over the limit because the additional speed consumed the margin of safety that the stopping distance required.

Vehicle Stability

Commercial trucks have a higher center of gravity than passenger vehicles, making them more susceptible to rollover during emergency maneuvers. A truck traveling above the speed limit that encounters a curve, an obstacle, or a sudden lane change by another vehicle must execute a steering correction at a speed the vehicle’s dynamics may not tolerate. The faster the truck is traveling, the greater the lateral forces generated during any steering maneuver, and the more likely those forces are to exceed the vehicle’s rollover threshold. Speed-related single-vehicle crashes involving truck rollovers are a direct consequence of this relationship.

As the IIHS has noted, speed increases the risk that an evasive steering maneuver will result in loss of control,¹⁷ a risk that is compounded for vehicles with a higher center of gravity, where the lateral forces generated during high-speed corrections can exceed the rollover threshold more quickly than in lower-profile vehicles.

Crash Energy

The kinetic energy of a moving vehicle equals one-half its mass multiplied by the square of its velocity. For an 80,000-pound truck, even a modest speed increase translates into an enormous increase in crash energy. A truck traveling at 70 mph carries approximately 16 percent more kinetic energy than the same truck at 65 mph. At 80 mph, the energy is approximately 33 percent greater than at 70 mph.

This additional energy must be absorbed by the vehicles, the occupants, and the roadside infrastructure involved in the crash. At some point, the energy exceeds the capacity of the vehicle structures and restraint systems to protect the occupants, and the crash becomes unsurvivable. For passenger vehicle occupants struck by a speeding truck, that threshold is reached at lower speeds than most people realize.

The Role of Speed Governors and Limiters

Many motor carriers equip their trucks with electronic speed limiters, also called speed governors, that cap the vehicle’s maximum speed at a carrier-determined threshold. A carrier that sets its speed limiter at 65 mph has made a policy decision that its trucks will not exceed that speed regardless of the posted limit. Carriers that adopt speed limiters typically do so for a combination of safety, fuel economy, and insurance cost reasons.

The existence of a speed limiter is relevant in litigation in two ways:

• First, if the truck involved in the crash was equipped with a speed limiter and the ECM data shows the truck was traveling above the limiter’s set speed, the data indicates that the limiter was either disabled, bypassed, or malfunctioning. This raises questions about whether the driver tampered with the system and whether the carrier monitored limiter compliance.
• Second, if the truck was not equipped with a speed limiter despite the carrier’s knowledge that its drivers routinely operated at speeds above the posted limit, the absence of a limiter becomes evidence that the carrier had a technologically available means of preventing speeding and chose not to use it.

The Federal Motor Carrier Safety Administration (FMCSA) and the National Highway Traffic Safety Administration (NHTSA) jointly proposed a federal rule mandating speed limiters on heavy commercial vehicles in September 2016. FMCSA issued an advance notice of supplemental proposed rulemaking in May 2022, signaling its intent to proceed with a carrier-focused speed limiter requirement.¹⁸ However, in July 2025, both agencies formally withdrew the proposed rule and the supplemental notice, citing significant policy and safety concerns, data gaps regarding potential safety benefits and economic impacts, and the potential displacement of state authority to set speed limits for heavy vehicles.¹⁹

The absence of a mandate does not eliminate the relevance of limiters in the negligence analysis. A carrier that knew its drivers were speeding, had the technology to prevent it, and chose not to deploy that technology made a decision that prioritized operational flexibility over safety. That decision is discoverable and relevant.