In 2024 forty-five people died in accidents involving a commercial truck on roads in Utah. As stated in UDOT’s own Truck Smart safety campaign, passenger vehicle drivers, not truck drivers, were at fault in 75 percent of the crashes in Utah that year that involved semi-trucks (see UDOT’s June 2025 announcement). Most people we speak to find this statistic surprising. People usually assume that when a crash happens near a semi, the truck caused the accident.
Data on national crashes confirms this same trend in the case of rear-end collisions. Figures from the federal FARS compiled by FMCSA show that in fatal crashes involving both a truck and a passenger vehicle, a rear-end collision occurred. The passenger vehicle hit the back of the truck more than three times as often as the truck hit the back of the passenger vehicle.
We’ve represented injured victims in truck cases. The first question almost every client asks us is some version of "Who's at fault?" The honest answer depends on which vehicle hit which, how much following distance existed, what the truck’s own onboard systems recorded, and whether either driver violated a specific Utah statute. This guide breaks down how authorities actually determine fault in a Utah rear-end truck accident. It uses the state’s traffic code, federal trucking regulations, and the physics that distinguish a truck crash from an ordinary two-car fender bender.
Most rear-end truck accidents fall into one of two very different sets of circumstances. In each scenario, responsibility points to a different party from the start.
| Scenario | Who Utah law presumes is negligent first | What usually decides the outcome | Defense the other side typically raises |
| A semi-truck rear-ends your car | The truck driver, as the trailing vehicle | Truck’s following distance, electronic logging device (ELD) speed data, brake and maintenance records | You stopped suddenly or unsafely in front of the truck |
| Your car rear-ends a semi or trailer | You, as the trailing vehicle | Whether the truck’s brake lights and turn signals worked, whether the truck stopped or merged without warning, trailer visibility and underride guard condition | You were following too closely or not paying attention |
On Utah's freight routes, both situations happen all the time. In each case the legal assumption is that the driver behind has the first view of who is at fault. The evidence and the outcome, however, which is why the sections below are just as important as the initial assumption.
The Utah Code section 41-6a-711 mandates that all drivers maintain a sufficient distance behind the vehicle in front of them "taking into account the speed of the vehicles, the traffic on the highway, and the condition of the highway.' It establishes a minimum following distance of at least two seconds. A driver who breaks this law and causes an accident thereby violates a safety rule written specifically to stop rear-end crashes. Utah courts treat that violation as clear proof of negligence whenever the breach leads to injury.
That same assumption applies whether the vehicle behind is a four-door sedan or an 80,000-pound tractor-trailer. It can also be refuted. Insurance adjusters employed by trucking companies regularly claim that the vehicle in front is at fault for stopping without reason. These include brake-checking, or for reversing into the truck's path. We have seen exactly the same argument used by an insurer in a case involving a passenger vehicle driver who said the semi-trucks in front merged or braked without warning. The law itself provides you with a means of countering the weak version of that defense. It clearly links a safe following distance to the 'condition of the highway.' A trucking company can't blame black ice in Parleys Canyon for a following distance that was already inadequate for the conditions.
Most rear-end collisions between two passenger cars follow a basic three-second following-distance rule. Trucks, however, are different because of their weight, length, and the lag of their air brakes. In its own guidance on the dangers of following too closely, the Federal Motor Carrier Safety Administration advises commercial drivers to keep a following distance of at least one second for every 10 feet of the length of the vehicle when travelling below 40 mph, to add one extra second when going over 40 mph, and to double that gap in wet or icy conditions.
| Rig length | Following distance below 40 mph | Following distance above 40 mph |
| 40-foot straight truck | 4 seconds | 5 seconds |
| 53-foot single semi-trailer | 5 to 6 seconds | 6 to 7 seconds |
| 70- to 80-foot combination rig | 7 to 8 seconds | 8 to 9 seconds |
In practice this is important since a truck driver who was tailgating a car on I-15 in Salt Lake County or who was going down the slope at Point of the Mountain was probably maintaining a distance of only one car length rather than one truck length. This makes it far easier to establish negligence than it would be to simply say that he was too close. According to the FMCSA's own analysis of the Large Truck Crash Causation Study, keeping too close a distance was a contributing factor in about 5 percent of all large truck crashes throughout the country, a figure that rises considerably on the steep, winding freight routes that pass through Utah's canyons.
A truck driver who is clearly at fault will in most cases not take full responsibility, which is the reason why this dispute is so important. Under Utah Code § 78B-5-818, a jury or claims adjuster assigns a percentage of fault to every party. Your own share of fault reduces your compensation, so long as that share stays at 50% or lower. If your fault exceeds 50%, Utah law bars you from recovering any damages.
Many people who have experienced crashes find it surprising that Utah has ended joint and several liability under Utah Code § 78B-5-820. This rule applies in rear-end truck cases that name more than one defendant.
For example, the driver and the trucking company, or a maintenance contractor whose negligence played a part, each defendant is only responsible for paying their own portion of the percentage of fault that the jury assigns them. This one rule is a major reason why the evidence described below, which clearly identifies who was responsible for causing the crash, is so important in a truck case in Utah.
A vehicle driving behind does not, by itself, rule out a claim against the truck or its carrier. In some cases, certain facts can shift the blame back to the truck, even when a car hits it from behind.
When these conditions apply, the trucking company bears direct liability. The employer also answers for its driver’s ordinary negligence under the respondeat superior doctrine. This is one of the reasons why truck accidents have greater significance than a typical fender bender. Federal regulations in 49 CFR Part 387 require interstate carriers transporting general freight to have at least $750,000 in liability coverage. This amount rising as high as $5 million in the case of hazardous cargo, as compared with the much lower minimum auto insurance limits set by Utah for an ordinary passenger vehicle.
While police reports and statements from people who saw the incident are important, in the case of truck rear-end collisions in Utah the decisions are generally based on data produced by the truck itself. The evidence that our firm asks for at the very beginning of almost every truck case consists of:
Trucking companies store most of this data on their servers. They can routinely erase or delete it within weeks after a crash. For this reason, a truck accident lawyer makes sending a formal evidence preservation letter one of their very first steps on your behalf.
The client feedback available on our testimonials page shows an average rating of 5.0 stars based on over 120 Google reviews. Mariana S. explained that Managing Attorney Kigan Martineau responded quickly to her first call and clearly laid out his options from the start. Andy G. also praised attorney Dan Benzion for his responsiveness and for actively advocating on his client's behalf. The reviews in question give an overview of the general experience clients have when working with our firm rather than referring to a particular truck case. As with any legal outcome, results vary depending on the specific facts of each individual claim.
Rear-end truck accidents can involve multiple factors, including following distance, driver actions, road conditions, and the size and weight of the vehicles involved. Determining who is responsible may require reviewing crash reports, vehicle damage, driver records, and other available evidence. If you were injured in a Utah truck accident, BAM Personal Injury Lawyers can help investigate the circumstances of the crash and explain your legal options. Contact us today for a free evaluation of your trucking injury claim.
If your vehicle is still drivable, move it to a safe place and call 911 right away. Utah Code § 41-6a-401 requires you to notify law enforcement whenever a collision causes injury or more than $2,500 in property damage. Truck crashes almost always exceed that threshold. Before anyone moves the truck, photograph the scene, the damage, and the truck’s DOT number and license plate. These details appear on the door and help identify the carrier. Do not discuss fault with the driver or anyone from the trucking company’s insurance team. Any statement you make can later be used to argue that both sides bear responsibility.
Yes, in most cases. The federal leasing rules in 49 CFR § 376.12 require a carrier operating under its own federal authority to assume exclusive possession, control, and full responsibility for any truck it leases for the entire duration of the lease. In most jurisdictions, courts have used this regulation to hold carriers liable for a leased driver’s negligence. It is under what is called the statutory employer doctrine, even if the driver entered into an independent contractor agreement. The term the company used in its documentation has seldom affected the result.
Right, in Utah each driver is required to have at least $3,000 worth of Personal Injury Protection (PIP) coverage. This PIP coverage will pay for your initial medical expenses and a part of your lost income no matter who was responsible for the accident. The coverage starts off right away, since it's important to note that investigations into truck accidents. Those involving the insurance company of a trucking business usually take a lot longer to settle than a straightforward two-car claim. After your damages go above Utah's serious injury limit—typically when medical costs exceed $3,000 or when a fracture or a permanent injury is involved. You can then claim on the at-fault party's liability insurance for the remainder of your losses. This include pain and suffering, even though PIP does not cover those.
Although a citation can help, it does not conclude the analysis. The traffic citation is a finding at the level of a criminal offense or infraction made by a trooper on the spot. Your civil claim for injury has to demonstrate negligence on the part of the other party by a preponderance of the evidence. This is the standard that is determined later after a more complete record of evidence has been assembled. Even after a citation is issued, the trucking company's insurers will still challenge fault. They'll argue that the officer did not have access to the ELD data, dash cam footage, or maintenance records, which only become available during a formal investigation. While the citation is significant evidence, the process of building the rest of the evidence usually settles the claim.
Often, yes. Utah’s following-too-closely statute explicitly ties a safe following distance to the “condition of the highway." A driver is expected to increase following distance and reduce speed as conditions worsen, not simply maintain the same gap and blame the weather afterward. Federal guidance for commercial drivers goes further, recommending that truckers double their following distance in rain, snow, or ice.
Generally, the law of the state where the crash physically occurred governs the claim, so a crash on I-15 just south of the Idaho line would typically be governed by Utah law even if you or the truck driver live elsewhere. That said, insurance coverage, the driver’s home state, and where the trucking company is based can complicate where you can file suit and which state’s procedural rules apply. Because our firm is licensed and handles cases in both Utah and Idaho, we can evaluate a border-area crash under both states’ laws and advise you on which forum gives you the stronger claim.
See also: Utah Rear-End Collision Lawyer: Liability, Injuries, and Maximizing Your Settlement, How Dash Cam Footage Proves Fault in a Utah Truck Accident Claim
Kigan Martineau is a Partner at BAM Personal Injury Lawyers and an accomplished trial attorney representing injury victims across Utah and Idaho. A graduate at the top of his class from American University Washington College of Law, Kigan specializes in complex motor vehicle crashes, commercial trucking litigation, and wrongful death claims. He achieved the highest settlement in Southern Utah history and has helped secure over $100 million in cumulative resolutions for the firm’s clients.
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