A truck underride crash happens when a car slides under the back or side of a tractor-trailer and the trailer crushes the passenger compartment. If a rear guard was missing, damaged or defective, or the truck was parked, lit or driven unsafely, the driver, the trucking company, the trailer owner or a manufacturer may be responsible for your losses. Most Georgia injury claims must be filed within two years (O.C.G.A. § 9-3-33).
Federal rules require rear impact guards on most trailers, but no federal rule currently requires side underride guards. Because a trailer bed sits at about windshield height, a car’s crumple zones and airbags may never engage, which is why these crashes are so often deadly. This guide explains the rules, the common causes, who may be liable and the evidence that decides these cases.
Key Takeaways
- Most trailers and semitrailers must have rear impact guards (49 C.F.R. § 393.86), and NHTSA strengthened the federal guard standards in a final rule published July 15, 2022.
- No federal standard requires side underride guards. NHTSA asked for public comment on the issue in 2023 and has said the question remains under review.
- The driver, the trucking company, the trailer owner, the guard or trailer manufacturer and a repair shop may all share responsibility.
- The trailer, its guard and the truck’s electronic data are key evidence, so a preservation letter should go out quickly.
- Georgia reduces your recovery by your share of fault and bars it at 50% or more (O.C.G.A. § 51-12-33).
Types of Truck Underride Crashes
- Rear underride: A car hits the back of a trailer and goes under it. This often happens when a truck stops suddenly, moves slowly or is stopped on or near the road at night.
- Side underride: A car goes under the side of a trailer, usually when a truck turns, changes lanes or pulls across a road or out of a driveway.
- Front override: A truck runs over the back of a smaller vehicle, usually in a rear-end crash.
In each case, the height difference between the trailer and the car is what makes the crash so dangerous. The strongest parts of a passenger car sit below the trailer bed, so the trailer can strike the windshield, roof pillars and the occupants’ heads.
Underride Guard Rules
- Rear guards: Federal rules require rear impact guards on most trailers and semitrailers (49 C.F.R. § 393.86), built to federal strength standards known as FMVSS 223 and 224. NHTSA’s 2022 final rule upgraded those standards so guards must help protect occupants of small passenger cars that strike the rear of a trailer at 35 mph, including crashes where only half of the car’s width overlaps the trailer.
- Maintenance: Motor carriers must systematically inspect, repair and maintain the vehicles they control, and a bent, rusted or badly repaired guard can fail at low speed.
- Side guards: No federal standard currently requires side underride guards. NHTSA published an advance notice of proposed rulemaking in April 2023, and when it denied a related safety petition in 2025, it said the issue was being addressed through its ongoing work under the Infrastructure Investment and Jobs Act.
- Lighting and reflective tape: Trailers must have required lamps and reflective markings so other drivers can see them at night.
The guard’s condition is some of the most important evidence in the case. You can read more about federal trucking rules on the FMCSA website.
Common Causes of Underride Crashes
- Missing, damaged or poorly maintained rear guards
- Missing reflective tape, broken lights or dirty markings that make a trailer hard to see at night
- Sudden or unnecessary braking
- Wide turns, U-turns and lane changes without checking blind spots
- Trucks pulling across a highway, or backing into a road, at night
- Trucks stopped on the shoulder or in a travel lane without warning devices
- Rain, fog and glare that cut visibility for everyone
Who Can Be Held Liable
- The truck driver, for unsafe stops, turns, lane changes or parking.
- The trucking company, for the driver’s conduct on the job and for its own failures in inspection, maintenance, training or hiring.
- The trailer owner or leasing company, if the trailer was poorly maintained.
- The trailer or guard manufacturer, if the guard was defectively designed or built.
- A maintenance or repair shop that inspected or repaired the guard or lights.
- Other drivers whose negligence contributed to the crash.
Georgia divides fault among everyone who caused the crash. Your recovery is reduced by any share of fault assigned to you, as long as you are less than 50% at fault (O.C.G.A. § 51-12-33). Georgia’s 2025 tort reform law (SB 68) also changed some trial rules. For example, evidence that a person was not wearing a seat belt may now be admitted on fault and causation, and a party may ask to try fault and damages separately. Learn more on our truck accident practice page and our page on Atlanta truck accident claims.
Injuries and What a Claim Can Include
Underride crashes often cause traumatic brain injuries, spinal cord injuries and paralysis, severe head, neck and facial injuries, and fatal injuries, especially in side underride crashes. A claim can include:
- Medical bills, rehabilitation and future care
- Lost wages and lost earning capacity
- Pain and suffering and loss of enjoyment of life
- For families, wrongful death damages measured by the full value of the life lost
- Punitive damages in limited cases involving willful misconduct or conscious indifference to consequences, generally capped at $250,000 with exceptions (O.C.G.A. § 51-12-5.1)
The Evidence That Decides Underride Cases
- The trailer and its guard: photos, measurements and the certification label, before the trailer is repaired or put back in service
- The truck’s electronic data: engine control module data, the electronic logging device (hours of service) and GPS
- Inspection and maintenance records for the trailer and guard
- Dashcam and nearby video, plus witness statements
- The police report and a crash reconstruction
Trucking companies often send investigators to the scene quickly. A lawyer can send a preservation letter so the trailer and data are not lost.
What to Do After an Underride Crash
- Call 911 and get medical care right away.
- Photograph the truck, the trailer’s rear or side, the guard and the lights, if you or someone with you can do so safely.
- Get the truck’s company name, USDOT number and trailer number, plus witness names.
- Be careful about giving a recorded statement to the trucking company’s insurer before you get advice.
- Talk to a lawyer quickly so the trailer and electronic data are preserved.
Most Georgia injury claims must be filed within two years of the crash, and wrongful death claims within two years of the death. If a government vehicle was involved, a written ante litem notice may be due much sooner. See our guide to Georgia personal injury deadlines.
Frequently Asked Questions
What Is a Truck Underride Accident?
It is a crash where a smaller vehicle slides under the back or side of a large truck or trailer. Because the trailer bed sits at about windshield height, the trailer often crushes the passenger compartment. These crashes can be fatal even at moderate speeds.
Are Underride Guards Required in Georgia?
Federal rules require rear impact guards on most trailers and semitrailers operating in Georgia and nationwide. Side underride guards are not currently required by federal law. Whether a missing or damaged rear guard contributed to your crash is a key question in many cases.
Who Is Liable for an Underride Crash?
It depends on what caused it. The truck driver, the trucking company, the trailer owner, the guard or trailer manufacturer and a maintenance shop can all share responsibility. Georgia law divides fault among everyone who contributed to the crash.
Can a Family Recover for a Fatal Underride Crash?
Yes. Georgia’s wrongful death law lets certain family members seek the full value of the life of the person who was killed, and the estate can seek medical and funeral costs. These claims generally must be filed within two years of the death.
Underride crashes are among the most serious truck cases, and the trucking company starts building its defense right away. If you or someone you love was hurt, The Gunn Law Group offers a free, no-obligation consultation, and there is no fee unless we recover for you. Call 888-BIG-GUNN (888-244-4866) or contact us online. Hablamos español.
