Most injury cases involve some argument over fault. The defense will often concede that the defendant did something wrong but argue the plaintiff did something wrong too — and that the plaintiff's share of the blame should reduce or eliminate any recovery. How that argument plays out depends entirely on which state's law applies. In Missouri the answer is generous to plaintiffs.
This article explains how Missouri's pure comparative fault rule works under RSMo §537.765, and what it means in practice when a jury divides up responsibility for an accident.
What Missouri changed in 1983
Until 1983, Missouri followed the old common-law rule of contributory negligence. Under that rule, any fault on the plaintiff's part — even one percent — barred recovery completely. A driver who was rear-ended in stopped traffic could lose at trial because a defense witness said the brake light was burned out. The rule produced harsh results, and the Missouri Supreme Court abandoned it in Gustafson v. Benda, 661 S.W.2d 11 (Mo. banc 1983).
The legislature codified the new rule the same year. Today, Missouri's comparative fault statute reads:
"In all actions, claims, counterclaims, and third-party claims for damages caused by fault . . . a defendant may plead and prove the fault of the plaintiff as an affirmative defense. Any fault chargeable to the plaintiff shall diminish proportionately the amount awarded as compensatory damages but shall not bar recovery." — RSMo §537.765.2
Three words in that statute matter: "shall not bar." A Missouri plaintiff is never completely barred from recovery by their own fault. Even a plaintiff found 99% at fault can recover one percent of the damages. That is the meaning of "pure" comparative fault.
How the math works at trial
A Missouri jury is given the case in two main pieces. First it determines the total damages — the dollar value of the plaintiff's medical bills, lost wages, pain and suffering, and so on. Second it allocates fault as percentages between the parties. The judge then applies the math: total damages multiplied by the defendant's share of fault equals the verdict.
Worked example: a Florissant plaintiff is rear-ended on Lindbergh. A jury finds her total damages to be $100,000. The jury also finds that the plaintiff was 30% at fault for stopping suddenly to avoid a deer, and the defendant was 70% at fault for following too closely and looking at his phone. Under RSMo §537.765, the plaintiff recovers $70,000 — her full damages reduced by her own share of fault.
The same math at the extremes: a plaintiff found 5% at fault on a $200,000 verdict recovers $190,000. A plaintiff found 80% at fault on the same verdict recovers $40,000. In every case, the plaintiff recovers something.
Why "pure" comparative fault is a meaningful protection
Many states — and the old Missouri common-law rule — barred a plaintiff entirely once their share of fault crossed some threshold. The pure rule rejects any threshold. A Missouri plaintiff at 51% fault still recovers 49% of the damages. A plaintiff at 80% fault still recovers 20%. That makes Missouri one of a relatively small number of pure-comparative jurisdictions, and it changes how cases are valued at every stage:
- Plaintiff 30% at fault on a $100,000 verdict: recovers $70,000.
- Plaintiff 50% at fault: recovers $50,000.
- Plaintiff 51% at fault: recovers $49,000.
- Plaintiff 70% at fault: recovers $30,000.
The practical effect is that a fault dispute in a Missouri case is almost never a question of whether to settle — it's a question of for how much. Defense counsel and adjusters know this. Good plaintiff's counsel uses it.
What "fault" actually means
Comparative fault is not just about who hit whom. The defense routinely argues plaintiff fault on theories like:
- Failure to wear a seatbelt. In Missouri, evidence of seatbelt non-use is generally inadmissible to reduce damages under RSMo §307.178.4 — a notable exception that protects unbelted plaintiffs.
- Speeding. Even if the defendant ran a stop sign, a plaintiff going 15 over the limit may bear some share.
- Distracted driving. Phone records, infotainment logs, and dashcam footage are routinely subpoenaed.
- Failure to keep a careful lookout. A driver with the right of way still has a duty to watch.
- Open-and-obvious hazards in premises cases. Stepping into a clearly marked construction zone shifts fault to the visitor.
The jury hears the evidence and assigns percentages. Good defense lawyers know that even small plaintiff-fault percentages add up. Good plaintiff's counsel anticipates these arguments and develops the record to defeat them.
Why this matters in settlement
Cases rarely go to trial. Most settle. But the settlement number is anchored to what a jury would likely do — and that calculation requires both sides to estimate the fault split. A case with clean liability settles near full damages. A case where the plaintiff plausibly bears 30% to 50% fault settles for proportionally less.
When an insurance adjuster offers a low number on a Missouri case, the explanation is often "we think your client is partly at fault." The right response is rarely to accept the number. The right response is to develop the evidence — police reports, witness statements, scene photos, dashcam, expert reconstruction — that pins fault on the defendant. We have written separately about why the first insurance offer is rarely the last word, and about how settlement values are actually built.
What this means for your case
If you were partly at fault in a Missouri injury case, you almost certainly still have a viable claim. Comparative fault is an argument about how much you recover, not whether you recover at all. A handful of practical points:
- Tell your lawyer everything. Hidden facts come out at deposition. The case strategy is built around the truth, not around what we wish were true.
- Do not admit fault at the scene. Apologies, even reflexive ones, get repeated by defense witnesses. Be polite, exchange information, call police.
- Preserve evidence early. Dashcam footage, surveillance video, and phone records have short retention windows. A litigation-hold letter on day three is worth more than a subpoena on day ninety.
- Choose the right forum. Where the crash happened, where the driver lives, and which county the case is filed in all affect outcomes. The right choice can be the difference between a recovery and a low-ball settlement.
Pure comparative fault is one of the more plaintiff-friendly features of Missouri tort law. It is also one of the most misunderstood — by clients, by adjusters, and sometimes by lawyers who do not work in this area regularly. If you have been hurt in a Missouri accident and someone has told you your fault bars recovery, get a second opinion. The statute says otherwise. For a broader picture of Missouri injury practice, see our personal injury overview and car accident page.
This article is general legal information for Missouri residents. It is not legal advice. Missouri law changes regularly — statutes are amended, case law evolves, and the application of any rule depends on the specific facts of each case. Do not act, or refrain from acting, based on this article without consulting a qualified Missouri attorney about your particular situation. Reading this article does not create an attorney-client relationship. For advice on your specific case, contact David Naumann & Associates at (314) 831-9350. The initial consultation is free. See the full Legal Disclaimer for complete terms.