Who Is at Fault in an Underride Accident- MO Law
- Kenneth Powell
- 4 days ago
- 6 min read
One of the most devastating types of car accidents is an underride truck accident. These are accidents that occur when a passenger vehicle crashes into the side or rear of a semi-truck, and it becomes stuck underneath. In many cases, the top of the smaller vehicle is removed in the process, which can lead to fatalities very quickly.
Trying to determine who is at fault in an underride accident might seem like an easy task, but it's really far from it. The investigation is often extremely detailed, and the legal process can take years to work through. The stakes are very high for victims of a truck underride accident, and only an experienced truck accident lawyer can help victims and families get through the process.
At Powell Law Firm, attorneys fight hard for accident victims when underride accidents happen. These accidents often have life-altering injuries, including fatal injuries, and victims and their families need an experienced attorney at their side.
Truck accident attorneys can help determine who is liable in a truck accident case, and they can help victims recover damages after an accident occurs. They can also advise on who is at fault in a roundabout accident MO.

What Is an Underride Accident?
Underride truck accidents occur when a car slides underneath large commercial trucks. Typically, this is a tractor-trailer, and the smaller car is pushed under the large truck during a collision. There are generally two types of underride accidents:
Rear Underride Collisions - A rear underride collision occurs when a car crashes into the back of a truck and then slides underneath it.
Side Underride Collisions - A side underride accident occurs when a smaller vehicle hits the side of a large truck and gets lodged under it.
Due to the difference in height between commercial vehicles and passenger vehicles, the top of the smaller vehicle is often crushed or torn off completely. This often leads to serious injuries, including severe head injuries, and many of these catastrophic injuries are deadly.
Common Causes of Underride Accidents in Missouri
Underride truck accidents can occur due to a variety of reasons. Distracted driving and driver error often play a role in these accidents, but other causes, such as equipment failure and improper safety measures, might also lead to issues. In many cases, there are several causes, such as high speeds, poor weather, and heavy truck traffic on Missouri highways.
Here are the most common causes of underride accidents:
1. Sudden Stops by the Truck Driver
If a driver suddenly stops without warning, especially on a highway where there are higher speeds, a car following behind the truck might not be able to stop in time. Instead, the driver of the car could slide under the trailer.
2. Poor Visibility or Weather Conditions
Poor weather conditions, such as rain, snow, fog, or low light, can reduce visibility. This increases the risk of a smaller vehicle crashing into a larger one. The chances are much higher when the truck driver doesn't have lights on or doesn't warn other drivers that the truck is stopped. Even if an underride truck accident doesn't occur, a jackknife accident might, which still will likely cause severe injuries.
3. Lack of Underride Guards
Federal regulations require that large trucks have rear impact guards, but not side underride guards. This means that passenger cars can get caught underneath a truck from the side since there is nothing stopping the car. It's possible that a rear end collision can occur, too, but since rear guards are required, many times the car won't go under the truck. Instead, they simply stop or get pushed into oncoming traffic, which is extremely dangerous.
4. Driver Inattention
Either driver can cause an underride accident due to driver inattention. Things like driver fatigue or distracted driving can put the driver of the passenger vehicle in extreme danger.
5. Brake Light or Reflector Failures
A truck that does not have working lights, or a vehicle that hasn't been maintained correctly could cause an accident, too. In this case, the driver might not be at fault. Instead, the truck maintenance company might be liable.
It's often difficult to determine who is at fault in these accidents, so it's imperative that victims consult with the best motor vehicle accident lawyer in St Louis as soon as possible.
Who Is at Fault in an Underride Accident in Missouri?
There are many factors that can go into determining fault in an underride accident. In Missouri, there is a comparative fault system, which means more than one party can be found to be at fault, and each party will be assigned a percentage of the blame. Compensation in an accident are awarded based on that percentage.
Who can be at fault in an underride truck accident? Any of the following:
1. The Truck Driver
The driver of the truck can be found to be at fault if they did any of the following:
Stopping suddenly without justification
Failing to use hazard lights or signs
Failing to yield the right of way
Driving impaired or distracted
A truck driver can hold full or partial fault in a car accident. In Missouri, truck drivers are required to follow strict regulations, and violating these can establish negligence.
2. The Trucking Company
The trucking company may also be at fault in a car accident if:
The company did not properly maintain the truck
There are no safety guards in place, or the guards are faulty
The company allowed an under-qualified driver to drive the truck
The driver was overworked or under pressure to meet unrealistic delivery deadlines
If a law firm like Powell Law Firm can prove that a St. Louis trucking company acted negligently in its hiring or supervision practices, liability may be shared.
3. The Passenger Vehicle Driver
The driver of the passenger car might also be at fault, even if they were severely injured or killed. The passenger car driver might be at fault in the following cases:
The driver was following too closely
Distracted driving or aggressive driving
Impaired by drugs or alcohol
Speeding or ignoring traffic laws
Since Missouri law states that fault can be shared, there may be situations where the victim might not be eligible for maximum compensation. For instance, if the driver was found to be 30% at fault, but the truck driver was found to be 70% at fault, the driver can still get compensation, but it will be 30% less.
4. Third Parties
It is also possible that another person altogether could cause the accident or be involved in the accident. For instance, a brake manufacturer might be found to be at fault if the brakes were determined to be faulty. A cargo loader might be found to be at fault if a load shifted due to incorrect loading. A defective truck part may cause the accident, or other vehicles on the road may cause the accident if they lose control and cause the truck or car to crash.
Evidence Used to Determine Fault in Underride Accidents
There are a number of pieces of evidence that can help prove fault in an underride truck accident. These include:
Police reports
Witness statements
Dashcam or other video footage
Truck driver logbooks
Electronic logging device data
Maintenance records
Roadway or weather conditions
Accident reconstruction
Medical records
Missouri Laws and Federal Regulations Affecting Underride Accidents
Here are the laws and regulations that can help determine who is at fault in an accident:
Missouri Comparative Fault Law
Missouri Revised Statutes § 537.765 explains how comparative fault works. Even if a victim is partially at fault, they can sill get fair compensation.
Federal Truck Safety Rules
The Federal Motor Carrier Safety Administration (FMCSA) requires that tractor trailers must have rear underride guards, but there is no requirement for side guards. If these guards are not in place, the driver and trucking company could be at fault.
Statute of Limitations in Missouri
There is a statute of limitations in Missouri following an accident. Victims have five years following the date of the accident to file a lawsuit.
Compensation for Victims of Underride Accidents
An underride crash is usually extremely serious, and victims often suffer from the following:
Traumatic brain injuries
Spinal cord injuries
Internal organ damage
Wrongful death
Powell Law Firm works to recover the full scope of damages from the responsible party, including:
Medical expenses/medical bills (past, present, and future medical expenses)
Lost wages and diminished earning capacity
Pain and suffering
Emotional trauma
Funeral and burial costs in wrongful death cases
Punitive damages (in cases of gross negligence)

Why Hire Powell Law Firm for an Underride Accident Claim?
Powell Law Firm has built a strong reputation in St. Louis, MO, for handling complex truck accident claims. Underride accidents require knowledge of both Missouri law and the specialized rules governing the trucking industry.
Following an underride truck accident, emergency medical attention should be the first priority. Following that, a thorough investigation into the cause of the crash is imperative. Victims require legal representation, and they choose Powell Law Firm because of the firms:
Aggressive investigation strategies
Access to expert witnesses and accident reconstructionists
Proven success against major trucking companies and insurers
Compassionate, client-first approach
Deep understanding of Missouri courts and jury expectations
Contact a St. Louis Underride Accident Attorney Today
The legal team at Powell Law Firm is here for victims of underride truck accidents in Missouri. Reach out to the team for a free consultation.
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