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Daily Driver Advocate
Verified: September 2026

Car Insurance Research: Shared Fault, Claim Disputes, and State Negligence Law

Can You Dispute an 80/20 Car Insurance Claim?

Last Verified: September 2026Independent Research Report

The letter is two paragraphs long. It says the adjuster has reviewed the statements and photos and has assigned 80% of the liability to one driver and 20% to the other. If you are the 20% driver, the other insurer is offering at most four-fifths of your repair bill, and in a contributory negligence jurisdiction such as Maryland even that 20% can bar recovery entirely. If you are the 80% driver, you may recover a fifth of your losses or nothing at all, depending on your state, and a surcharge could follow at renewal. The letter reads like a verdict, but nobody testified and no judge signed it. So can you dispute an 80/20 car insurance claim?

Yes. An 80/20 split is the insurer’s estimate, not a court ruling. You can ask for its basis in writing, submit new evidence, escalate, file with your own insurer, use state rating appeals where they exist, or sue the other driver.

That answer holds in every state. What changes from state to state is what a dispute is worth and which door to knock on. Moving from 20% to 10% on a $10,000 claim is worth $1,000 almost everywhere a claimant can recover at all. Moving from 80% to 50% can be worth $5,000 in one state and nothing in the state next door. And the regulator you might call first will, in most states, tell you plainly that it does not decide fault. This report maps each route: what the insurer owes you in writing, how the negligence rules turn percentages into dollars, how your own insurer can carry the fight, where rating appeals exist, and when court is the only place left.

Research Summary

Three Numbers Behind a Fault-Split Dispute

1.1 million
Insurer-vs.-Insurer Arbitration Filings in 2025

Members of Arbitration Forums, Inc., the industry’s not-for-profit intercompany forum, filed 1.1 million arbitration disputes and 2.3 million subrogation demands in 2025, worth almost $27 billion in claims.[9]

>50%
Fault Share Before an At-Fault Rating in CA and MA

California requires at least 51% of the legal cause before a “principally at-fault” finding, and Massachusetts defines an at-fault accident as one where the operator was more than 50% at fault. A 20% driver clears both lines.[19][20]

$677
Value of 10 Fault Points on an Average Property Damage Claim

ISO data reported by the Insurance Information Institute put the average 2024 property damage liability claim at $6,770 (excluding Massachusetts, Michigan and New Jersey; severity includes loss adjustment expenses). As an illustration, where both fault shares still permit recovery, 10 points shifts about one-tenth of that. Above a modified-comparative bar it can be worth $0; crossing the bar can be worth far more.[31][12]

First, Which Side of the 80/20 Are You On?

Comparative fault — the rule that splits the cost of a crash according to each driver’s share of blame — is what produces a number like 80/20. The Illinois Department of Insurance gives the standard illustration: if the other driver is 80% at fault and you are 20% at fault, “you can collect for your damages.”[3]Idaho’s regulator describes the same practice from the insurer’s side: a company “may determine that both parties are partially at-fault and assign a percentage of fault to each involved motorist.”[4]

“Disputing an 80/20 claim” means opposite things depending on which number is yours. The 20% driveris mostly not at fault. The other driver’s liability insurer offers 80% of that driver’s losses, and the dispute goal is to push the share toward zero. Each point moved is a point of the claim recovered.

The 80% driver is mostly at fault. Depending on the state, that share either bars recovery from the other driver outright or cuts it to 20%, and it commonly counts as an at-fault accident for rating. What a dispute is worth depends on which rule applies. In a pure comparative fault state such as Washington, every point still counts: moving from 80% to 70% on $10,000 in damages raises the recovery from $2,000 to $3,000.[10] In a modified comparative fault state, points shaved while the share stays above the bar change nothing; the dispute pays only if the evidence carries the share below the legal line, 50% or 51%, where the consequences flip.

Either way, the percentage is not a measurement. It is an adjuster’s judgment built from statements, photos, the police report, traffic-law presumptions and experience. Two adjusters can read the same file and land on different numbers. The research on how insurers determine fault covers that investigation in detail; this report picks up where the letter arrives.

One Crash, Up to Four Separate Payments

A two-car shared-fault crash can set up to four money flows in motion, and each can be disputed on its own track. Knowing which flow the letter is about tells you who to argue with.

  1. Your claim against the other driver’s liability coverage. Paid by the other insurer, reduced by your share of fault.
  2. The other driver’s claim against your liability coverage.Paid by your insurer, reduced by that driver’s share or barred entirely, depending on state law. Under the standard policy your insurer “will settle or defend, as we consider appropriate,” so it controls this one.[2]
  3. Your own collision claim.The standard policy’s collision coverage pays for direct and accidental loss to your car, minus the deductible, without regard to who caused the crash.[2]
  4. Subrogation.After paying you, your insurer steps into your shoes under the policy’s “Our Right To Recover Payment” clause and may pursue the other insurer, including your deductible, reduced by your share of fault.[2]

The first flow is the one most drivers mean when they say they are disputing a split. The fourth can be an effective place to fight it, when your insurer chooses to pursue it, for reasons covered below.

What the Split Is Worth Depends on Your State’s Negligence Rule

The adjuster supplies the percentage; the law of the state where the crash happened decides what that percentage pays. American states fall into four broad families, and the differences cluster at two points on the scale: 0% and 50%.

The table applies one example law from each family to the same hypothetical: you have $10,000 in damages and the other driver bears whatever share of fault you do not.

Worked Example

What $10,000 in Damages Becomes Under Each Negligence Rule

Amount recoverable on $10,000 of damages in a two-driver crash when the claimant is 10%, 20%, 50%, 51% or 80% at fault, under pure comparative fault, a 51% bar, a 50% bar, and contributory negligence, with example state laws for each rule.
RuleExample LawYou 10%You 20%You 50%You 51%You 80%
Pure comparative faultWashington (RCW 4.22.005): contributory fault diminishes the award proportionately “but does not bar recovery.” New York keeps this rule for property damage under CPLR 1411(a).[10][11]$9,000$8,000$5,000$4,900$2,000
Modified comparative, 51% barTexas (§ 33.001): no recovery if the claimant’s responsibility is “greater than 50 percent.” Pennsylvania (§ 7102) and Florida (§ 768.81(6)) use the same line. New York’s CPLR 1411(b) now bars a claimant whose fault is greater than the defendant’s in personal injury actions subject to Insurance Law article 51 commenced on or after May 26, 2026.[12][13][14][11][32]$9,000$8,000$5,000$0$0
Modified comparative, 50% barUtah (§ 78B-5-818(2)): recovery only from defendants whose fault “exceeds” the claimant’s, so an even split pays nothing.[16]$9,000$8,000$0$0$0
Contributory negligenceMaryland (Coleman, 2013): the state’s highest court declined to abolish the common-law rule that a claimant’s own contributing negligence bars recovery.[17]$0$0$0$0$0
Calculation: recovery = $10,000 × (100% − your fault share), set to $0 where the example law’s bar applies. Illustrative two-party arithmetic; ignores policy limits, deductibles, no-fault benefits and multi-party allocation. Example jurisdictions only; not a 50-state compilation. Verified: September 2026.

Read the table from the 20% driver’s seat first. In every comparative fault family, that driver collects $8,000, and every 10 points knocked off the share is another $1,000. The one exception is the bottom row. Under contributory negligence, a claimant whose own negligence contributed to the crash in any degree recovers nothing, so a 20% finding is as fatal as an 80% one. Maryland’s highest court reaffirmed that rule in 2013 and left any change to the legislature.[17]A 50-state compilation by the law firm Matthiesen, Wickert & Lehrer (a secondary source) also lists Alabama, North Carolina, Virginia and the District of Columbia as contributory negligence jurisdictions for car-versus-car crashes.[18] In those places, the dispute is about zero, not about points.

Now read it from the 80% driver’s seat. Under pure comparative fault, each point moved is worth $100 on this claim. Under a 51% or 50% bar, 80% and 60% pay the same thing: nothing, and the only move that changes the outcome is getting across the line. Under Texas’s statute a claimant recovers nothing if their responsibility is “greater than 50 percent,” so a 50/50 split pays half.[12]Under Utah’s statute, recovery runs only against defendants whose fault “exceeds” the claimant’s, so the same 50/50 split pays zero.[16]One point in the adjuster’s allocation can decide the entire claim.

Two recent changes show that the rule, not the facts, can move the value. Florida’s 2023 civil remedies law added § 768.81(6): “any party found to be greater than 50 percent at fault for his or her own harm may not recover any damages,” outside medical negligence cases.[14] Section 30 of that act applies it, except as otherwise provided, to causes of action filed after March 24, 2023.[15]New York followed in 2026 with a narrower change. CPLR 1411 still says a claimant’s own fault does not bar recovery for injury to property, but new subsection (b) bars a claimant in a personal injury action subject to Insurance Law article 51 — New York’s no-fault motor vehicle law — whose culpable conduct is greater than that of the defendant or defendants.[11] The New York Department of Financial Services states the amendment took effect May 26, 2026 and applies to actions and proceedings commenced on or after that date.[32] For a New York 80% driver, the car repair claim still pays 20%. An injury lawsuit commenced on or after May 26, 2026 and subject to article 51 recovers nothing at 80%; an action commenced before that date follows the earlier pure comparative rule.

What the Insurer Owes You in Writing

A dispute starts with the insurer’s reasoning, because you cannot rebut facts you have not seen. Any driver can ask for that reasoning in writing; whether the insurer must provide it, and in what detail, depends on the state. The NAIC’s Model Unfair Claims Settlement Practices Act (Model 900) — a template that states adopt, modify or decline, not a nationwide law — lists as an unfair practice “failing in the case of claims denials or offers of compromise settlement to promptly provide a reasonable and accurate explanation of the basis for such actions.”[1] An 80/20 offer is, functionally, a compromise settlement. Even where a state has enacted similar language, the model reaches only acts committed flagrantly or often enough to indicate a general business practice, creates no private cause of action, and is enforced by the regulator.

New York is unusually specific. Under 11 NYCRR § 216.10, an insurer handling a third-party property damage claim under a motor vehicle liability policy must explain New York’s comparative negligence rules in its acknowledgment letter, and “any offer based on comparative negligence shall contain a factual and complete explanation of the insurer’s basis for apportioning culpability.”[6]The written offer or denial is generally due within 10 business days after the investigation is complete, with a decision within six months of the notice of loss. Both time limits drop away under § 216.10(g) when there is objective evidence that anyone in the accident who may assert a bodily injury claim against the insured sustained a “serious injury” under Insurance Law § 5102; those property damage claims are settled or denied under § 216.6 instead. An 80/20 letter from a New York insurer that states only the percentages is missing something the regulation requires.

California’s Fair Claims Settlement Practices Regulations are less specific for third-party claims: an insurer that “disputes liability or damages” on a third-party claim must do so in writing, but the regulation does not add New York’s “factual and complete explanation” language. A first-party denial in California must list “all bases” for the decision with the factual and legal basis for each.[7]Florida adds a rating-side version: on request, the insurer and agent must supply “the complete proof of fault or other criteria which justifies the additional charge.”[24]

How to Dispute an 80/20 Split, Step by Step

The steps run roughly in the order they pay off. Not every step fits every claim; the first question is always which insurer made the call and which money flow it controls.

  1. Identify the decision and the stakes.Is the split coming from the other driver’s insurer (your claim against them), your own insurer (your liability, your collision recovery, or your rating), or both? Then price it: 10 points of your damages, your deductible, a possible surcharge, and whether a 50%, 51% or contributory bar is in play.
  2. Ask for the basis in writing.Request the specific facts, statements and traffic rules the adjuster relied on. Where your state imposes an express explanation duty, such as New York’s for comparative-negligence property damage offers, cite it.[1][6]
  3. Answer the specific fact, not the conclusion.Most splits start from a presumption — the rear driver, the left-turning driver, the driver pulling out — and adjust for evidence about the other driver. A short letter that names the fact the adjuster got wrong, attaches the proof (photos of damage location and final rest, dash-camera video, witness names and contact details, the police report, the outcome of any citation) and states the percentage you think is correct gives the adjuster something to move on.
  4. Follow the tickets.Convictions carry weight in the rating rules. California presumes a driver not principally at fault when only the other driver was convicted of a moving violation, and Florida and Pennsylvania give similar weight to the other driver’s conviction.[19][24][23] A dismissed ticket of your own is also a listed Florida reimbursement ground.
  5. Escalate inside the company. Ask for a supervisor or claims-manager review of the liability decision, in writing, with your evidence attached.
  6. Consider your own collision coverage. If the other insurer will not move, let your own insurer pay and pursue it, as described in the next section.
  7. Use rating appeal rights if a surcharge follows.See the state table below for California’s 30-day reconsideration request and the Massachusetts Board of Appeal.
  8. Complain to the regulator about process failures.A complaint about your own insurer (no explanation, missed deadlines, ignored evidence, a deductible left out of subrogation) is the kind a department is most able to act on. Complaints about the other driver’s insurer get less traction in some states: Texas, for example, says it generally cannot help when another person’s insurer will not accept liability.[5]
  9. Go to court if the numbers justify it. Small claims court against the other driver for vehicle damage within the limit, or an attorney for larger and injury claims, with the limitations deadline in view.

If negotiation stalls entirely, the research on negotiating with a car insurer and the research on when an insurer can deny a claim cover the adjacent rules.

Letting Your Own Insurer Carry the Fight

For a 20% driver with collision coverage, an effective dispute can start with a claim rather than an argument. You file with your own insurer, pay your deductible, and your car is fixed. Your insurer is then subrogated to your claim and may pursue the other carrier for what it paid; if it does, the party arguing for 0% is a company with its own money on the line. Pursuit is the insurer’s choice. California requires an insurer to tell a first-party claimant in writing whether it intends to pursue subrogation, and if it elects not to, or stops, to state that any recovery is the claimant’s responsibility.[7]

Qualifying disputes between companies that have signed the Arbitration Forums, Inc. agreements may go to intercompany arbitration there. Signatory companies agree to compulsory arbitration of covered auto disputes up to $100,000 in total company-paid damages, with the deductible not counted toward that limit. Arbitrators apply the local jurisdiction’s law, so the negligence rule from the table above follows the claim into the forum, and decisions are final and binding without rehearing or appeal except for clerical or jurisdictional errors.[8] The volume is large: 1.1 million arbitration disputes filed in 2025.[9]

Three features of that forum matter to you. First, you are not a party. The insureds do not file, attend or appeal, and the deductible appears in the decision only as a courtesy calculation. Your leverage is getting your best evidence to your own insurer’s subrogation unit before it files. Second, the decision does not bind you elsewhere: it is neither res judicata nor collateral estoppel — legal doctrines that stop the same issue from being relitigated — for other claims or suits from the same accident.[8] An 80/20 arbitration result on the car does not decide your injury claim or a small claims suit for uncovered losses.

Third, the deductible follows the split. California requires that every subrogation demand include the first-party claimant’s deductible and that the insurer share recoveries with the claimant “on a proportionate basis.”[7] As an illustration, picture a California driver with a $1,000 deductible, assigned 20% fault. If the insurer pursues subrogation and recovers 80% of the loss from the other carrier, about $800 of the deductible comes back. If it recovers less, or does not pursue, less or none comes back through that route. If the share is pushed to 0% and the full loss is recovered, the full $1,000 does. Deductible-reimbursement rules differ by state, so ask your insurer in writing what percentage it is pursuing and how it will share the recovery.

Appraisal Settles the Price, Not the Blame

Drivers are often told to “invoke appraisal.” The clause exists, but it answers a different question. Part D of the standard ISO personal auto policy provides that “if we and you do not agree on the amount of loss, either may demand an appraisal.” Each side hires an appraiser, the two pick an umpire, and a decision agreed to by any two is binding; each side pays its own appraiser and splits the umpire’s cost.[2]

The trigger is the amount of loss under your own policy. Appraisal does not decide fault, and it does not reach a claim against the other driver’s insurer. It still has a place in an 80/20 dispute: 80% of a lowball estimate is less than 80% of a correct one, so the valuation and the percentage are two separate numbers worth checking.

What a State Insurance Department Will and Will Not Do

Regulators are candid about their limits. The Idaho Department of Insurance “does not have the authority to determine who is at-fault for an accident.”[4]The Texas Department of Insurance lists “decide who was at fault in an accident” among the things it cannot do, along with helping with complaints against another person’s insurance company and making a company pay a claim unless not paying violates a law or the policy.[5]Illinois will review a complaint and contact the insurer but “cannot make a determination of comparative negligence.”[3]

That makes a complaint a tool for process, not for percentages, and it works best against your own insurer. Good grounds include an insurer that never explained its split, missed a claims-handling deadline, ignored evidence you submitted, or left your deductible out of its subrogation demand. Where the problem is the other driver’s insurer refusing to accept liability, Texas says it likely cannot help, and other states may take a similar view; check your own department’s complaint rules. In Texas, a company has 15 days to respond to a complaint and can request a 10-day extension.[5]

Suing the other driver’s insurer directly is generally not an option either. In Moradi-Shalal v. Fireman’s Fund(1988), the California Supreme Court held that Insurance Code § 790.03(h), the state’s unfair claims practices provision, does not create a private cause of action against an insurer, overruling an earlier decision that had allowed third-party claimants to sue.[25]The practical routes against the other driver’s insurer are negotiation, your own insurer’s subrogation, or a suit against the driver. Disputes with your own insurer are different; the research on suing your own car insurance company covers those.

When the Split Follows You to Renewal

The claim payout is one consequence; the premium is another. Surcharges are governed by state rating law and each insurer’s filed plan, and several states tie “at fault” to a threshold. That is why the same 80/20 crash can surcharge the 80% driver and leave the 20% driver untouched. It is also where some of the only formal, government-run fault reviews exist.

State Law Comparison

Shared Fault and Premium Surcharges in Five States

For California, Massachusetts, New York, Pennsylvania and Florida: the fault standard for an at-fault rating or surcharge, the dollar threshold, and the built-in route for disputing it.
StateFault StandardDollar ThresholdDispute Route
California“Principally at fault”: the driver’s actions or omissions were at least 51% of the legal cause.Bodily injury or death, or property damage over $1,000.Written notice of the finding and its basis; request reconsideration within 30 days; a different employee decides and answers in writing within 30 days.[19]
MassachusettsOperator “more than 50%” at fault, applying the 211 CMR 74 standards of fault.Claim payment over $1,000 for accidents on or after July 1, 2015 ($500 before).Appeal to the Board of Appeal within 30 days of the date on the insurer’s notice, with the appeal form and filing fee.[20][21]
New YorkNo surcharge for an incident where the insured or insurer received reimbursement or a judgment equal to one-third or more of the insured’s property damage claim, so a 20% driver whose property damage claim is paid at 80% would generally fall within that exception. A bodily injury surcharge is governed separately and requires that the insured was at fault.Property damage: no points or surcharge for aggregate property damage of $2,000 or less, unless two or more property damage accidents in the experience period. This threshold does not govern bodily injury surcharges.Refund of the surcharge for all affected policy periods if the accident is later shown to fall within an exception in the insurer’s plan.[22]
PennsylvaniaNo surcharge where the insured “was not at fault in causing or contributing to the accident.”Set by the insurer’s approved rating plan; no percentage stated in the regulation.Listed not-at-fault situations, including a rear-end hit with no conviction and an accident where only the other driver was convicted.[23]
FloridaSurcharge only if the insurer’s file lets it determine in good faith that the insured was “substantially at fault.”No dollar threshold in the cited paragraph.Reimbursement on listed grounds, including a written statement of facts showing lack of fault that the file does not rebut; on request, the insurer must supply the complete proof of fault.[24]
Compiled from the official regulation and statute text in the Primary Source Directory. Five states shown for comparison; not a 50-state compilation. Each insurer’s filed rating plan also applies. Verified: September 2026.

California and Massachusetts give the 80% driver the most structured route. California requires written notice of a principally-at-fault finding and its basis, a reconsideration on request within 30 days, and a written answer within 30 days from an employee other than the one who made the original call.[19] Massachusetts sends the appeal to its Board of Appeal, which treats the 211 CMR 74 standards of fault as presumptively determinative unless rebutted by persuasive evidence.[21]For rating in both states, the 80% driver’s target is the 50% line. That rating line is separate from the recovery rule: California’s 51% threshold governs only whether an insurer may classify the accident as principally at fault, while damages between the drivers follow the state’s pure comparative fault rule, so moving from 80% to 70% can raise a California recovery without changing the rating result.[19][33] The research on whether a not-at-fault accident raises your premium and the research on whether other insurers can see your claims cover what happens to the record afterward.

Court: The Only Forum That Finally Decides Fault

Every route above ends in the same place if it fails. “If a settlement cannot be reached,” the Illinois regulator writes, “the courts make the final determination of comparative negligence.”[3]The suit is normally filed against the other driver, whose insurer typically defends it. A judge or jury sets the percentages fresh, bound neither by the adjuster’s 80/20 nor by an intercompany arbitration result.[8]

For vehicle damage, small claims court is often the practical venue. California allows individuals to sue for up to $12,500 (businesses up to $6,250) and does not allow lawyers to represent parties. A plaintiff who loses on their own claim cannot appeal it, but a defendant ordered to pay can appeal, and a plaintiff who loses on the defendant’s counterclaim can appeal that decision; appeals must be filed within 30 days of the notice of entry of judgment. For the driver bringing the claim, that means the first hearing is the only one, so the evidence should be ready before filing.[26] Texas justice courts hear claims up to $20,000, excluding statutory interest and court costs but including attorney fees.[27] The research on suing the driver who hit your car covers the mechanics.

The clock runs while you negotiate. California allows three years for “an action for taking, detaining, or injuring goods or chattels,” which covers vehicle damage.[28] Texas requires suit for injury to the property of another, or for personal injury, within two years after the cause of action accrues.[29] An open claim file does not pause either deadline.

Evidence rules can also differ from the negotiating table. A police report carries weight with an adjuster, but in Florida a crash report made by a person involved in the crash, and statements that person made to an officer to complete it, “may not be used as evidence in any trial, civil or criminal.”[30] Witnesses, photos and video that can be authenticated in court are what carry a fault case past settlement.

Scope and Limitations

This report covers private passenger auto claims in the 50 United States and the District of Columbia. State examples illustrate the range of approaches; a rule stated for one state describes that state alone, and neither table is a 50-state compilation. The NAIC model act is a template that states adopt, modify or decline. Policy language quoted is the 06 98 edition of ISO form PP 00 01 as published by a state regulator; your own policy controls. No-fault states pay certain injury benefits through personal injury protection regardless of fault, which limits how much of an injury claim turns on the split but does not change who pays for vehicle damage. Arbitration Forums figures are the organization’s own reported numbers. The contributory negligence list outside Maryland is drawn from a labeled secondary source. Deductible reimbursement rules outside California were not surveyed.

Questions Readers Ask Next

Is an 80/20 fault split final once the adjuster sends the letter?

No. The split is the insurer’s settlement position, not a court judgment. The Illinois Department of Insurance says that if a settlement cannot be reached, “the courts make the final determination of comparative negligence.” Until a claim is settled and released, or a court rules, the percentage can be renegotiated with new evidence.

Will my state insurance department decide who was at fault?

Generally no. The Idaho Department of Insurance states it “does not have the authority to determine who is at-fault for an accident,” and the Texas Department of Insurance lists deciding fault among the things it cannot do. Illinois’s department can contact the insurer and ask it to review its determination but cannot make a comparative negligence determination itself. Complaints are most useful for process failures: no explanation, missed deadlines, or ignored evidence.

If I am 20% at fault, do I get my deductible back?

Possibly part of it, but only if your insurer pursues subrogation and recovers from the other insurer. In California, 10 CCR § 2695.7(p) requires the insurer to tell you in writing whether it intends to pursue subrogation, and § 2695.7(q) requires every subrogation demand to include your deductible and any recovery to be shared with you on a proportionate basis. As an illustration, if the insurer recovers 80% of the loss, about $800 of a $1,000 deductible would come back. Rules in other states vary.

Does being 20% at fault put an at-fault accident on my record?

Not in every state. California will not let an insurer find a driver “principally at fault” for rating purposes below 51% of the legal cause (10 CCR § 2632.13), and Massachusetts defines an at-fault accident as one where the operator was more than 50% at fault (211 CMR 134.02). Pennsylvania bars a surcharge only where the insured was not at fault in causing or contributing to the accident, so a 20% share there depends on the insurer’s filed plan.

Can I sue the other driver’s insurance company over the split?

In most cases the lawsuit is against the other driver, not the other driver’s insurer, and that insurer typically defends and pays any judgment within the policy limits. In Moradi-Shalal v. Fireman’s Fund (1988), the California Supreme Court held that the state’s unfair claims practices statute does not create a private right of action against an insurer, and the NAIC model act states it creates no private cause of action.

Can appraisal fix an unfair fault percentage?

No. The appraisal clause in the standard ISO personal auto policy applies when “we and you do not agree on the amount of loss.” It resolves the value of the damage under your own physical damage coverage, not who caused the crash. It can still matter indirectly, because 80% of an undervalued estimate is less than 80% of an accurate one.

Legal Disclaimer

This content is provided for informational and educational research purposes only. It does not constitute legal advice, insurance advice, or a coverage or fault determination, and it does not create an attorney-client relationship. Statutes, regulations, policy forms, court limits and industry arbitration rules change; verify current requirements with the official code of the state involved, your state insurance regulator, and your own insurer, and consult an attorney licensed in the relevant jurisdiction about a specific accident or deadline.

Primary Source Directory

  1. Unfair Claims Settlement Practices Act, Model 900 (Model law): National Association of Insurance Commissioners. Section 1 states that nothing in the Act creates or implies a private cause of action. Section 3 makes a Section 4 act an improper claims practice if committed flagrantly and in conscious disregard of the Act or with such frequency as to indicate a general business practice. Section 4(L): failing, in the case of claims denials or offers of compromise settlement, to promptly provide a reasonable and accurate explanation of the basis for such actions.
    NAIC — Model Law 900 (Official PDF) — opens a PDF in a new tab ↗
  2. Personal Auto Policy, ISO form PP 00 01 06 98 (Standard policy form published by a state insurance regulator): Nevada Division of Insurance. Part A: the insurer “will settle or defend, as we consider appropriate, any claim or suit.” Part D Insuring Agreement: pays for direct and accidental loss to the covered auto, minus any applicable deductible. Part D Appraisal: “If we and you do not agree on the amount of loss, either may demand an appraisal of the loss”; each party selects a competent appraiser, the two select an umpire, a decision agreed to by any two is binding, and each party pays its appraiser and shares the appraisal and umpire expenses equally. Part F — Our Right to Recover Payment: the insurer is subrogated to the rights of a person it pays who has a right to recover damages from another.
    Nevada Division of Insurance (policy form, PDF) — opens a PDF in a new tab ↗
  3. Comparative Negligence (State regulator consumer guidance): Illinois Department of Insurance. Gives the 80%/20% example in which the 20% driver can collect for damages; states the Department will review complaints and contact insurers but cannot make a determination of comparative negligence; and states that if a settlement cannot be reached, the courts make the final determination of comparative negligence.
    Illinois Department of Insurance — Comparative Negligence (Official) — opens in a new tab ↗
  4. Common Auto Claims Questions (State regulator consumer guidance): Idaho Department of Insurance. States that a company may determine both parties are partially at fault and assign a percentage of fault to each motorist, and that the Department does not have the authority to determine who is at fault for an accident.
    Idaho Department of Insurance — Common Auto Claims Questions (Official) — opens in a new tab ↗
  5. Auto Insurance Complaint (State regulator consumer guidance): Texas Department of Insurance. Lists things TDI cannot do, including decide who was at fault in an accident, help with complaints against another person’s insurance company, and make a company pay a claim unless not paying violates a law or the policy terms; states companies have 15 days to respond to a complaint and can request a 10-day extension.
    Texas Department of Insurance — Auto Insurance Complaint (Official) — opens in a new tab ↗
  6. 11 NYCRR § 216.10 — Standards for prompt, fair and equitable settlement of third-party property damage claims under motor vehicle liability insurance contracts (State regulation text): New York Department of Financial Services (Regulation 64); text reproduced by the Legal Information Institute. Subsection (a) requires the acknowledgment to explain New York’s comparative negligence rules; subsection (e) requires a written offer or denial within 10 business days of completing the investigation, and (e)(1) requires any offer based on comparative negligence to contain a factual and complete explanation of the insurer’s basis for apportioning culpability; subsection (f) requires a decision within six months of the notice of loss. Subsection (g) makes the (e) and (f) time limits inapplicable where there is objective evidence available for review by Department of Financial Services examiners that anyone involved who may assert a bodily injury liability claim against the insured sustained a serious injury as defined in Insurance Law § 5102; such claims are settled or denied under § 216.6.
    Legal Information Institute — 11 NYCRR § 216.10 — opens in a new tab ↗
  7. Cal. Code Regs., tit. 10, § 2695.7 — Standards for prompt, fair and equitable settlements (State regulation text): California Insurance Commissioner; text reproduced by the Legal Information Institute. Subsection (p): every insurer must notify a first-party claimant in writing whether it intends to pursue subrogation, and if it elects not to pursue or discontinues pursuit, must state that any recovery is the claimant’s responsibility. Subsection (b)(1): a first-party denial must be in writing with a statement listing all bases and the factual and legal bases for each; an insurer that denies a third-party claim or disputes liability or damages must do so in writing. Subsection (q): every subrogation demand must include the first-party claimant’s deductible, and recoveries must be shared with the claimant on a proportionate basis unless the claimant has otherwise recovered the whole deductible.
    Legal Information Institute — 10 CCR § 2695.7 — opens in a new tab ↗
  8. Reference Guide to Arbitration Forums, Inc.’s Agreements and Rules (Industry arbitration rules): Arbitration Forums, Inc. Describes compulsory arbitration among signatory companies; Rule 1-3 monetary limit of $100,000 in total company-paid damages in the Automobile forum, excluding the deductible; decisions based on applicable local jurisdictional law, final and binding without rehearing or appeal except for clerical or jurisdictional errors; decisions are neither res judicata nor collateral estoppel to other claims or suits; insureds are not parties, and the deductible is included as a courtesy calculation. Industry source, cited for the organization’s own rules.
    Arbitration Forums, Inc. — Reference Guide (PDF) — opens a PDF in a new tab ↗
  9. About Us (Industry organization statement): Arbitration Forums, Inc. Describes itself as a membership-driven, not-for-profit organization founded by the insurance industry in 1943 with over 5,100 members, and reports that in 2025 members filed 1.1 million arbitration disputes and 2.3 million subrogation demands collectively worth almost $27 billion in claims. Self-reported figures.
    Arbitration Forums, Inc. — About Us — opens in a new tab ↗
  10. Revised Code of Washington § 4.22.005 — Effect of contributory fault (Official statute text): Washington State Legislature. Contributory fault chargeable to the claimant diminishes proportionately the amount awarded as compensatory damages, but does not bar recovery.
    Washington State Legislature — RCW 4.22.005 (Official) — opens in a new tab ↗
  11. New York Civil Practice Law and Rules § 1411 — Damages recoverable when contributory negligence or assumption of risk is established (Official statute text): New York State Senate. Subsection (a): except as provided in subsection (b), in an action for personal injury, injury to property or wrongful death, the claimant’s culpable conduct does not bar recovery, and damages are diminished in proportion to it. Subsection (b): in an action for personal injury subject to article fifty-one of the insurance law, the claimant’s culpable conduct bars recovery if it is greater than that of the person, or combined persons, against whom recovery is sought.
    New York State Senate — CPLR 1411 (Official) — opens in a new tab ↗
  12. Texas Civil Practice and Remedies Code § 33.001 — Proportionate responsibility (Official statute text): Texas Legislature. In an action to which the chapter applies, a claimant may not recover damages if his percentage of responsibility is greater than 50 percent.
    Texas Constitution and Statutes — CPRC ch. 33 (Official) — opens in a new tab ↗
  13. 42 Pa.C.S. § 7102 — Comparative negligence (Official statute text): Pennsylvania General Assembly. Subsection (a): a plaintiff’s contributory negligence does not bar recovery where it was not greater than the causal negligence of the defendant or defendants, with damages diminished in proportion.
    Pennsylvania General Assembly — 42 Pa.C.S. § 7102 (Official) — opens in a new tab ↗
  14. Florida Statutes § 768.81 — Comparative fault (Official statute text): Florida Legislature. Subsection (6): in a negligence action to which the section applies, any party found to be greater than 50 percent at fault for his or her own harm may not recover any damages; the subsection does not apply to medical negligence actions under chapter 766.
    Online Sunshine — Fla. Stat. § 768.81 (Official) — opens in a new tab ↗
  15. Chapter 2023-15, Laws of Florida (CS/CS/HB 837, “Civil Remedies”) (Session law): Florida Legislature. Approved by the Governor March 24, 2023. Adds § 768.81(6). Section 30 applies the act, except as otherwise provided, to causes of action filed after its effective date.
    Laws of Florida — Ch. 2023-15 (Official PDF) — opens a PDF in a new tab ↗
  16. Utah Code § 78B-5-818 — Comparative negligence (Official statute text): Utah State Legislature. Subsection (2): a person may recover from any defendant or group of defendants whose fault, combined with that of immune persons and nonparties to whom fault is allocated, exceeds the fault of the person seeking recovery.
    Utah State Legislature — Utah Code § 78B-5-818 (Official) — opens in a new tab ↗
  17. Coleman v. Soccer Association of Columbia, No. 9, September Term 2012 (Official court opinion): Court of Appeals of Maryland (now the Supreme Court of Maryland), filed July 9, 2013. The Court declined to abrogate the common-law defense of contributory negligence, treating the change as a matter for the legislature.
    Maryland Judiciary — Coleman v. Soccer Ass’n of Columbia (Official PDF) — opens a PDF in a new tab ↗
  18. Contributory Negligence/Comparative Fault Laws in All 50 States (Secondary source — law firm compilation): Matthiesen, Wickert & Lehrer, S.C. Lists Alabama, Maryland, North Carolina, Virginia and the District of Columbia as pure contributory negligence jurisdictions, noting a District of Columbia exception for non-motorized users. Cited for context only; the compilation predates the 2023 Florida and 2026 New York changes described above.
    Matthiesen, Wickert & Lehrer — 50-state chart (PDF) — opens a PDF in a new tab ↗
  19. Cal. Code Regs., tit. 10, § 2632.13 — Determination of “Principally at-Fault” Accidents (State regulation text): California Insurance Commissioner; text reproduced by the Legal Information Institute. Subsection (b) bars a principally-at-fault determination unless the driver’s actions or omissions were at least 51 percent of the legal cause and the accident caused bodily injury or death or more than $1,000 in property damage. Subsection (c) lists rebuttable presumptions that a driver is not principally at fault, including where the driver was not convicted of a moving violation and the other driver was. Subsection (e) requires written notice of the determination and its basis and reconsideration on request within 30 days by a different employee or agent, with a written decision within 30 days.
    Legal Information Institute — 10 CCR § 2632.13 — opens in a new tab ↗
  20. 211 CMR 134.02 — Definitions, Safe Driver Insurance Plan (State regulation text): Massachusetts Division of Insurance; text reproduced by the Legal Information Institute. Defines an At-fault Accident as one in which the involved operator was more than 50% at fault and the claim payment exceeded $500 (accidents before July 1, 2015) or $1,000 (on or after July 1, 2015); defines the experience period as the six years preceding the policy effective date.
    Legal Information Institute — 211 CMR 134.02 — opens in a new tab ↗
  21. 211 CMR 88.03 — Appeals of Insurer At-fault Accident Determinations (State regulation text): Massachusetts Division of Insurance; text reproduced by the Legal Information Institute. Gives an involved operator who disagrees with an insurer’s at-fault accident determination the right to appeal to the Board of Appeal; makes the 211 CMR 74.04 standards presumptively determinative unless rebutted by persuasive evidence; requires the appeal form and filing fee within 30 days of the date on the insurer’s notice.
    Legal Information Institute — 211 CMR 88.03 — opens in a new tab ↗
  22. 11 NYCRR § 169.1 — Merit rating plan procedures (State regulation text): New York Department of Financial Services; text reproduced by the Legal Information Institute. Subsection (a): an accident not resulting in aggregate property damage over $2,000 shall not result in points or a surcharge, unless the insured has two or more property damage accidents in the experience period. Subsection (c): a bodily injury surcharge only if the insured was at fault. Subsection (g): an insured may not be surcharged for an incident for which the insured or the insurer has received reimbursement or a judgment equal to one-third or more of the value of the insured’s property damage claim. Subsection (h): refund of the surcharge, for all policy periods since its inception, if the accident is later established to fall within an exception in the insurer’s plan.
    Legal Information Institute — 11 NYCRR § 169.1 — opens in a new tab ↗
  23. 31 Pa. Code § 67.33 — Assessment of premium surcharge (State regulation text): Pennsylvania Insurance Department; text reproduced by the Legal Information Institute. An insurer may not assess a surcharge for a claim arising from accidents where the insured was not at fault in causing or contributing to the accident; lists situations deemed not at fault, including a lawfully parked vehicle, a rear-end collision without a conviction of the insured, a moving-violation conviction of the other driver only, and a hit-and-run reported within 24 hours.
    Legal Information Institute — 31 Pa. Code § 67.33 — opens in a new tab ↗
  24. Florida Statutes § 626.9541(1)(o) — Illegal dealings in premiums (Official statute text): Florida Legislature. Subparagraph 3.a. bars an additional premium or nonrenewal solely because of an accident unless the insurer’s file supports a good-faith determination that the insured was substantially at fault; 3.b. requires reimbursement or renewal on listed grounds, including (V) the other operator alone was convicted of a moving violation, (VII) the insured’s citation was dismissed or nolle prossed, and (VIII) a written statement from the insured establishing lack of fault that is not rebutted by the insurer’s file. Subparagraph 5. requires the insurer and agent, on request, to supply the complete proof of fault justifying the additional charge.
    The Florida Senate — Fla. Stat. § 626.9541 (Official) — opens in a new tab ↗
  25. Moradi-Shalal v. Fireman’s Fund Insurance Companies, 46 Cal. 3d 287 (1988) (Court opinion): Supreme Court of California. Held that Insurance Code § 790.03(h) does not create a private civil cause of action against an insurer that commits the enumerated unfair claims practices, overruling Royal Globe Insurance Co. v. Superior Court (1979).
    Justia — Moradi-Shalal v. Fireman’s Fund (opinion text) — opens in a new tab ↗
  26. Small Claims in California (State court self-help guidance): Judicial Council of California, California Courts Self-Help Guide. Individuals may sue for up to $12,500 and businesses up to $6,250; parties cannot be represented by a lawyer. The appeals page states that you can only appeal when you owe money, so usually only the defendant can appeal; a plaintiff who lost on the defendant’s counterclaim can appeal that decision; appeals must be filed within 30 days after the Notice of Entry of Judgment.
    California Courts — Small claims in California (Official) — opens in a new tab ↗
    California Courts — Appeal a small claims decision (Official) — opens in a new tab ↗
  27. Small Claims Maximum (State law library guidance): Texas State Law Library. The maximum in Texas small claims (justice) court is $20,000 under Government Code § 27.031, excluding statutory interest and court costs but including attorney fees, per Texas Rule of Civil Procedure 500.3(a).
    Texas State Law Library — Small Claims Maximum (Official) — opens in a new tab ↗
  28. California Code of Civil Procedure § 338 (Official statute text): California Legislature. Within three years: (c)(1) an action for taking, detaining, or injuring goods or chattels, including an action for the specific recovery of personal property.
    California Legislative Information — CCP § 338 (Official) — opens in a new tab ↗
  29. Texas Civil Practice and Remedies Code § 16.003 — Two-year limitations period (Official statute text): Texas Legislature. Subject to listed exceptions, a person must bring suit for trespass for injury to the estate or to the property of another, conversion of personal property, taking or detaining the personal property of another, or personal injury not later than two years after the day the cause of action accrues.
    Texas Constitution and Statutes — CPRC ch. 16 (Official) — opens in a new tab ↗
  30. Florida Statutes § 316.066 — Written reports of crashes (Official statute text): Florida Legislature. Subsection (4): except as specified, each crash report made by a person involved in a crash, and any statement made by that person to a law enforcement officer for the purpose of completing a required crash report, is without prejudice to the person reporting and may not be used as evidence in any trial, civil or criminal.
    The Florida Senate — Fla. Stat. § 316.066 (Official) — opens in a new tab ↗
  31. Facts + Statistics: Auto insurance (Industry data compilation): Insurance Information Institute, reporting ISO (a Verisk Analytics business) data. For 2024: 2.50% of insured drivers had a property damage liability claim, average $6,770; 0.80% had a bodily injury liability claim, average $28,278; 4.16% of collision policyholders had a collision claim, average $5,489. Table notes: the property damage liability series excludes Massachusetts, Michigan and New Jersey, and claim severity includes loss adjustment expenses. Industry data, cited for illustrative claim-size context only.
    Insurance Information Institute — Facts + Statistics: Auto insurance — opens in a new tab ↗
  32. Insurance Circular Letter No. 3 (2026): Motor Vehicle Insurance Reforms (State regulator guidance): New York Department of Financial Services, July 1, 2026. Explains the Part EE amendment adding CPLR § 1411(b), under which, in an action for personal injury subject to Insurance Law article 51, the claimant’s culpable conduct bars recovery if it is greater than that of the person or persons against whom recovery is sought; states the amendments took effect May 26, 2026 and apply to all actions and proceedings commenced on or after May 26.
    New York DFS — Circular Letter No. 3 (2026) (Official) — opens in a new tab ↗
  33. CACI No. 405 — Comparative Fault of Plaintiff (Official state jury instruction): Judicial Council of California. If the defendant proves the plaintiff was negligent and that the negligence was a substantial factor in causing the plaintiff’s harm, the plaintiff’s damages are reduced by the jury’s determination of the percentage of the plaintiff’s responsibility, with no bar at any percentage, reflecting California’s pure comparative fault rule.
    Judicial Council of California — Civil Jury Instructions, 2026 edition (Official PDF) — opens a PDF in a new tab ↗