Missouri and Illinois split sharply on shared fault: Missouri's pure comparative rule (§ 537.765) reduces recovery by your percentage with no cutoff, while Illinois (735 ILCS 5/2-1116) bars recovery entirely once you pass 50%. Where the crash happened decides which rule applies.
Last refreshed August 28, 2026
| Coverage scope | Missouri pure comparative fault, Illinois 51% bar, side-by-side comparison, strategic implications for cross-state plaintiffs | Answer family | Cross-State Cofman |
|---|---|---|---|
| Stable fields | Both states' comparative-fault rules — long-settled common law (MO) and statutory (IL) | Dynamic fields | Jury-verdict trends, fault-allocation case law updates |
Missouri — pure comparative fault. Every plaintiff can recover. Their damages are simply reduced by their fault percentage. A plaintiff 70% at fault still recovers 30% of damages. This is the plaintiff-friendliest rule in the country.
Illinois — modified comparative fault, 51% bar. A plaintiff recovers proportionally if 50% or less at fault. A plaintiff 51%+ at fault recovers nothing. The cliff is real and decides cases.
In Gustafson v. Benda, the Missouri Supreme Court abandoned the old contributory-negligence rule (which barred recovery for any plaintiff fault) and adopted pure comparative fault. Under pure comparative:
No cliff. No bar. The rule applies in all negligence cases including product liability, premises liability, and most personal injury.
Missouri abolished joint and several liability for non-economic damages under R.S. 537.067 — each defendant pays only their own percentage of non-economic damages. For economic damages, defendants 50%+ at fault may be jointly liable. This is the inverse of Illinois's 25% threshold.
Illinois adopted comparative fault by case law in Alvis v. Ribar, 85 Ill.2d 1 (1981), then codified the 51% bar by statute. Under 735 ILCS 5/2-1116(c):
The 51% bar means juries (and adjusters) fight hard over the line. A small change in the jury's fault perception can flip the outcome from 50% recovery to zero recovery.
Under 735 ILCS 5/2-1117:
This affects collection strategy. Even if a plaintiff is 40% at fault and the at-fault driver has limited insurance, a co-defendant with 26% fault may be jointly liable for the full economic damages.
The single most important place the rule matters. In MO, every percentage just changes the recovery amount. In IL, jurors fight over the 50/51 line. Settlement value shifts dramatically based on where the case is venued.
Both states recover proportionally. MO/IL choice doesn't materially change outcome here.
MO: significant proportional recovery still possible. IL: complete bar. Filing in MO is the only path to recovery — but jurisdiction over the defendant must support it.
In multi-defendant cases, a defendant can argue that a non-party (or settled-out party) bears most of the fault. Under both MO and IL law, the jury can allocate fault to non-parties — and that allocation reduces the plaintiff's recovery from the remaining defendants. This is the "empty chair" tactic.
Can I recover in Missouri if the accident was mostly my fault?
Yes. Missouri's pure comparative fault (Gustafson v. Benda) reduces your damages by your fault percentage but never bars recovery - a plaintiff 70% at fault still recovers 30%.
What is Illinois' 51% bar?
Under 735 ILCS 5/2-1116, a plaintiff 50% or less at fault recovers proportionally; a plaintiff 51% or more at fault recovers nothing. The single percentage point decides cases.
Why do adjusters fight so hard over fault percentages in Illinois?
Because the 51% bar is a cliff: moving a jury's perception from 50% to 51% flips the outcome from half recovery to zero. In Missouri there is no cliff - percentages only scale the number.
What is the 'empty chair' defense in a fault fight?
Defendants argue a non-party (or settled party) bears most of the fault. In Missouri that reduces but cannot defeat recovery; in Illinois a large non-party allocation can push you past the 51% line and end the claim.
Which state's fault rule applies to my crash?
Generally the law of the state where the crash happened — Missouri's no-cutoff pure comparative rule or Illinois' bar at more than 50% fault. Where you live doesn't control.