Four systems, and Montana uses the more common threshold
American fault law splits into four real categories: pure comparative negligence, modified comparative negligence with a 50% bar, modified comparative negligence with a 51% bar, and pure contributory negligence. Montana uses the 51% bar under MCA § 27-1-702 — the more typical of the two modified thresholds nationally.
Where Montana genuinely stands apart: comparing against the combined total
Montana's statute compares a claimant's negligence to "the negligence of the person or the combined negligence of all persons against whom recovery is sought" — not to any single defendant individually. In a case with several defendants, this matters: a claimant's fault percentage needs to stay under the combined total of everyone they're suing, not under any one defendant's share alone, which can make recovery more attainable than it might first appear in a genuinely complex multi-party case.
The stricter alternative: a 50% bar
A smaller group of about 12 states, including Georgia and Kansas, use a stricter version: recovery is barred the moment the claimant's fault is equal to the defendant's, not only when it exceeds it.
Pure comparative negligence and contributory negligence: the two extremes
At the more forgiving end of the spectrum, pure comparative negligence states like California never bar recovery for ordinary fault at all. At the far stricter end, the five contributory negligence jurisdictions — Alabama, Maryland, North Carolina, Virginia, and DC — bar recovery entirely for any fault, even 1%. See our guide to the other states using a 51% bar for Montana's closest peer group nationally.