Comparative negligence rules in Montana

If the other driver's insurer keeps telling you the crash was partly your fault, there's a reason behind it. In Montana, the percentage of blame assigned to you directly changes how much you can collect, and past a certain point it can wipe out your claim entirely. Knowing where that line sits, and what can and can't be counted against you, is the difference between accepting a lowball number and holding out for what your case is worth.

The 51% bar

Montana follows a modified comparative negligence rule. Under Mont. Code Ann. 27-1-702, your own negligence does not bar you from recovering damages "if the contributory negligence was not greater than the negligence of the person or the combined negligence of all persons against whom recovery is sought."¹ Two things follow from that sentence.

First, you can be partly at fault and still recover. Your award just gets reduced by your share. If a jury decides your damages are $100,000 and puts 20% of the blame on you, you collect $80,000. The statute requires that any damages "be diminished in the proportion to the percentage of negligence attributable to the person recovering."¹

Second, there is a hard cutoff. If your share of the fault is greater than the other side's, you recover nothing. In a straightforward two-car crash where you're suing one driver, that makes 50% the highest your own fault can be while you still collect. Reach 51% and the door closes. People call this the 51% bar, though the more exact way to put it is that you're fine as long as your fault is not greater than the other side's. At an even 50/50 split you still collect half, because 50 is not greater than 50.¹

That one word, "greater," is where a lot of Montana claims are won and lost. An adjuster who nudges your share from 49% to 51% does more than trim your payout. At 51% you collect nothing at all.

Who decides your percentage

Until a case is tried, nobody has actually fixed your fault percentage. The number an adjuster attaches to you early on is an estimate, and a self-interested one. If the case reaches a jury, the jury assigns the percentages. Everything before that is negotiation dressed up as arithmetic.

Because the statute compares your fault to the other driver's, small factual disputes swing real money. A claim where you're pegged at 30% is worth 70 cents on the dollar; the same claim at 55% is worth zero. Insurers know this, which is why early fault assignments tend to run high.

That matters because the facts driving the number are usually contested: who had the right of way, and whether a light was yellow or red when someone entered the intersection. Scene photos and the official crash report carry weight here, which is one reason to get the documentation early. Montana crash reports are here.

What can't be counted against you

One thing Montana law takes off the table: your seat belt. Under Mont. Code Ann. 61-13-106, evidence of whether you were wearing one "is not admissible in any civil action for personal injury or property damage resulting from the use or operation of a motor vehicle, and failure to comply ... does not constitute negligence."² Even in a state that fines you for riding unbelted, the at-fault driver's insurer cannot argue that your injuries are partly your own doing because you skipped the belt. That argument, routine in some other states, never reaches a Montana jury.

When more than one person is to blame

Real crashes often pull in more than two vehicles, or a driver plus a road-condition problem or a vehicle defect. Montana divides liability among multiple defendants under Mont. Code Ann. 27-1-703. The starting rule is that each defendant is jointly and severally liable for the award, with a right to seek contribution from the others.³ But a threshold changes the exposure for a minor defendant: a party found to be "50% or less" of the combined negligence is severally liable only, so it pays just its own percentage and nothing more.³ A defendant found more than 50% at fault can be left holding the larger shared portion.

For you as the injured person, the combined-fault language in 27-1-702 is the part to watch. Your fault is measured against everyone you're suing put together, not against each defendant one at a time. If you're 40% at fault, one driver is 35%, and another is 25%, your 40% is not greater than their combined 60%, so you still recover, reduced by your 40%.¹

The empty chair

Defendants in Montana can also point at people who aren't in the courtroom. Under Mont. Code Ann. 27-1-705, the trier of fact "shall consider the fault of persons not a party to the action" when there's admissible evidence of that fault.⁴ A defendant who wants to do this must affirmatively plead comparative fault and name each person it blames, either in the answer or within a reasonable time after, as the court allows.⁴ Lawyers call this the empty chair defense: the defendant shifts blame onto an absent driver, a phantom vehicle, or a company that already settled, shrinking its own share. Fault assigned to a nonparty isn't money you can collect from that nonparty in this case, so it can quietly cut what you take home.

Why the fault fight is really about insurance limits

Your percentage only matters if there's money behind the claim. Montana requires every driver to carry at least $25,000 per person and $50,000 per crash in bodily injury liability, plus $20,000 in property damage, under Mont. Code Ann. 61-6-103.⁵ Those are floor numbers, and a serious injury blows past them fast. Montana also requires insurers to offer uninsured and underinsured motorist coverage matching your liability limits unless you reject it in writing, under Mont. Code Ann. 33-23-201.⁶ If the at-fault driver is underinsured, or your own comparative share eats into a thin policy, your UM/UIM coverage is often what's left to make you whole. Damage to the car itself, including any diminished value after repairs, runs on a separate track; Montana's diminished value rules cover that.

Deadlines that end the argument

None of this helps if you wait too long. A personal injury claim in Montana has to be filed within 3 years of the crash under Mont. Code Ann. 27-2-204.⁷ Claims for damage to your vehicle and other property carry a shorter 2-year window under Mont. Code Ann. 27-2-207.⁸ Miss the deadline and the fault percentages stop mattering, because the court won't hear the case at all.

Comparative fault is contested evidence rather than settled fact, and how it's presented changes the result. If your share is genuinely in dispute, or an insurer is inflating it to get you over the 51% line, that's the moment to talk to someone who handles Montana crash claims. You can find a personal injury attorney here.

This is general information, not legal advice.

Sources

1. Mont. Code Ann. 27-1-702 (comparative negligence). https://mca.legmt.gov/bills/mca/title_0270/chapter_0010/part_0070/section_0020/0270-0010-0070-0020.html

2. Mont. Code Ann. 61-13-106 (seat belt evidence not admissible). https://mca.legmt.gov/bills/mca/title_0610/chapter_0130/part_0010/section_0060/0610-0130-0010-0060.html

3. Mont. Code Ann. 27-1-703 (multiple defendants, several and joint liability). https://mca.legmt.gov/bills/mca/title_0270/chapter_0010/part_0070/section_0030/0270-0010-0070-0030.html

4. Mont. Code Ann. 27-1-705 (several liability, nonparties). https://mca.legmt.gov/bills/mca/title_0270/chapter_0010/part_0070/section_0050/0270-0010-0070-0050.html

5. Mont. Code Ann. 61-6-103 (mandatory liability insurance). https://mca.legmt.gov/bills/mca/title_0610/chapter_0060/part_0010/section_0030/0610-0060-0010-0030.html

6. Mont. Code Ann. 33-23-201 (uninsured and underinsured motorist coverage). https://mca.legmt.gov/bills/mca/title_0330/chapter_0230/part_0020/section_0010/0330-0230-0020-0010.html

7. Mont. Code Ann. 27-2-204 (tort statute of limitations). https://mca.legmt.gov/bills/mca/title_0270/chapter_0020/part_0020/section_0040/0270-0020-0020-0040.html

8. Mont. Code Ann. 27-2-207 (property damage statute of limitations). https://mca.legmt.gov/bills/mca/title_0270/chapter_0020/part_0020/section_0070/0270-0020-0020-0070.html