Missouri Comparative Fault Explained

Under § 537.765 RSMo, Missouri abolished contributory fault as a complete bar to recovery and adopted the doctrine of pure comparative fault. This means that in any personal injury case, your compensation is reduced by your percentage of fault — but it is never eliminated entirely based on fault alone.

The math is straightforward. If your total damages are $100,000 and you are found 20% at fault, you recover $80,000. If you are 50% at fault, you recover $50,000. If you are 80% at fault, you recover $20,000. Even at 99% fault, you recover 1% of your damages.

This system applies to all negligence-based personal injury claims in Missouri, including car accidents, truck accidents, motorcycle accidents, slip and falls, and other injury cases. The statute was originally enacted for products liability claims, but the Missouri Supreme Court extended it to all negligence actions through subsequent case law.

Example 1: You are rear-ended at a stoplight, but you did not have your brake lights on. A jury awards $150,000 in damages and assigns you 10% fault for the brake light issue. You recover $135,000.

Example 2: You are injured in a highway merge accident. The other driver failed to yield, but you were exceeding the speed limit. A jury awards $300,000 and assigns you 40% fault. You recover $180,000. In a state with a 50% bar rule, this same recovery would be available — but if your fault were just 10 percentage points higher, you would recover nothing in those states. In Missouri, you would still recover $150,000.

Example 3: You slip on an icy sidewalk outside a business. The business failed to salt the walkway, but you were wearing inappropriate footwear and looking at your phone. A jury awards $80,000 and assigns you 60% fault. You recover $32,000. In most modified comparative fault states, this claim would be worth zero. In Missouri, you still receive compensation.

Example 4: A multi-vehicle pileup involving three drivers. The jury assigns 50% fault to Driver A, 30% to Driver B, and 20% to you. On a $500,000 verdict, you recover $400,000. Each defendant is responsible for their proportionate share of your reduced award.

Fault determination is a fact-intensive process that considers all available evidence. Police reports are often the starting point — the responding officer's assessment of the accident scene, statements from drivers, and any citations issued all factor into the fault analysis. But police reports are not conclusive; they are one piece of the puzzle.

Witness testimony can shift fault percentages significantly. An independent witness who saw the accident from a nearby car or sidewalk carries more weight than the drivers' own accounts, which are naturally self-serving. If your accident was captured on a dashcam, traffic camera, or nearby security camera, that footage can be decisive.

In complex cases — particularly truck accidents, multi-vehicle collisions, and high-value claims — accident reconstruction experts may be retained to analyze physical evidence, vehicle damage patterns, skid marks, road conditions, and vehicle data recorders (black boxes) to determine each party's contribution to the accident.

The insurance company will conduct its own investigation. Their adjuster will review the police report, take recorded statements, inspect vehicles, and review medical records. Keep in mind that the insurer's goal is to assign as much fault to you as possible to reduce your payout. This is why preserving evidence and consulting an attorney early matters.

If your case goes to trial, the jury is specifically instructed to assign a percentage of fault to each party found to be negligent. Jurors examine all the evidence — driver actions, speed, road conditions, visibility, traffic signals, and any other contributing factors — and reach a collective determination.

The jury's fault allocation directly determines the mathematical reduction of the damages award. If the jury assigns you 35% fault on a $200,000 verdict, the court enters judgment for $130,000. There is no judicial override or adjustment — the jury's percentages are applied precisely.

In cases with multiple defendants, the jury assigns separate fault percentages to each party. This means the total must add up to 100%. For example, in a chain-reaction crash, the jury might assign 60% to the driver who caused the initial collision, 25% to a second driver who failed to brake, and 15% to you for following too closely.

Missouri's pure comparative fault system stands in stark contrast to the modified comparative fault systems used in many surrounding states. This difference can dramatically affect the value of your claim depending on where the accident occurred.

Kansas uses a modified comparative fault system with a 50% bar. If you are found 50% or more at fault in Kansas, you recover nothing. A plaintiff who is 49% at fault recovers 51% of their damages, but a plaintiff at 50% fault recovers zero. Cross State Line Road from Missouri into Kansas, and the same accident with the same injuries could be worth hundreds of thousands of dollars — or zero.

Illinois also uses a modified system with a 50% bar as of 2025. Iowa uses a 51% bar (you are barred at 51% or more). Arkansas uses a modified system with a 50% bar. Nebraska uses a modified system with a 50% bar as well. Among Missouri's neighbors, only Missouri uses the pure comparative fault approach, making it the most favorable state in the region for plaintiffs who bear some fault.

This distinction matters most in cases where liability is genuinely shared. A rear-end collision where you were completely stopped will be 100% the other driver's fault in any state. But accidents involving speeding, lane changes, distracted driving, or poor visibility often result in shared fault — and in those cases, Missouri's pure system protects your right to recover.

Insurance companies in Missouri use comparative fault as a primary tool to reduce settlements. The adjuster will look for any evidence that you contributed to the accident — speeding, distracted driving, failure to wear a seatbelt, failure to seek prompt medical treatment — and argue that your fault percentage should be higher.

In settlement negotiations, the insurer does not have a jury to assign fault percentages. Instead, both sides argue about what a jury would likely find. If the insurer believes a jury would assign you 40% fault, they will discount their offer by 40%. Your attorney's job is to present evidence that minimizes your fault percentage and maximizes the defendant's.

This is why evidence preservation is critical from day one. Dashcam footage, witness contact information, photographs of the scene, and a detailed police report all help establish the other party's fault. The less evidence available, the more room the insurer has to argue that you bear a larger share of responsibility.

Under § 537.765 RSMo, the plaintiff's fault is an affirmative defense. This means the defendant — not you — bears the burden of proving that you were partially responsible for the accident. You do not have to prove that you were blameless; the defendant must prove that you were not.

In practice, this means the defendant must present specific evidence of your fault. Vague allegations are not enough. The defendant needs to show, through testimony, physical evidence, or expert analysis, that specific actions or omissions on your part contributed to the accident or your injuries.

This procedural protection matters more than it might seem. It shapes how cases are built, how discovery is conducted, and how settlement negotiations unfold. The defendant cannot simply claim you were 50% at fault — they must prove it with evidence, and the jury evaluates that evidence against the evidence you present showing the defendant's fault.