Liability: who was at fault, and how clearly
A negligence claim generally requires showing that someone owed a duty of care, breached it, and caused the injury. When fault is clear — a driver who ran a red light in front of witnesses — the discussion focuses on damages. When fault is disputed, the risk that a jury might find no liability affects what each side is willing to accept.
Shared fault matters too. Most states use some form of comparative fault, reducing recovery by the injured person’s own share of responsibility. Some states bar recovery once that share passes a threshold, and a few use contributory negligence, under which even slight fault can bar recovery. The thresholds differ by state, as our State Law Resources show.
Quality of evidence
Photos, video, witness statements, police or incident reports, and prompt medical records all make the facts harder to dispute. Missing evidence does not make a claim invalid, but uncertainty tends to be reflected in negotiations. See Organizing Evidence and Medical Records.
Injury severity and treatment pattern
- Nature and permanence of the injury. Objective findings (such as a fracture on imaging) are typically easier to establish than injuries diagnosed mainly from reported symptoms.
- Timing of first treatment. A long delay before seeing a doctor can be used to argue the injury was minor or caused by something else.
- Consistency. Gaps in treatment, missed appointments or not following medical advice can be raised as arguments that losses were not caused by the accident or were not reasonably limited.
- Future care. A documented need for future treatment can significantly affect the evaluation.
Pre-existing conditions
An earlier injury or condition in the same body area does not by itself defeat a claim. Many jurisdictions allow recovery for aggravation of a pre-existing condition, but the claim is typically limited to the worsening caused by the accident. See Pre-Existing Conditions and Injury Claims.
Insurance and collectibility
The at-fault party’s liability limits often set a practical ceiling, because many individuals do not have assets beyond their insurance that could realistically be collected. Your own underinsured motorist coverage may add another layer in vehicle cases. See Insurance Policy Limits.
Jurisdiction and type of defendant
State law governs deadlines, fault rules, damage caps, whether billed or paid medical amounts are recoverable, and special rules for claims against government entities. Claims against a city, county, state agency or public transit authority often require a formal notice of claim within a short window and may be subject to damage limits.
Timing and procedural posture
Settling before treatment ends risks undervaluing future needs; waiting too long risks missing a legal deadline. Whether a lawsuit has been filed, and how close a trial date is, also affects negotiation dynamics.
Representation and communication
Whether a claimant has a lawyer, and what is said to insurers, can affect a claim. Statements to adjusters and posts on social media can be used to question the extent of an injury. This is not a reason to be untruthful — credibility is one of the most important assets in any claim — but it is a reason to be careful and consistent.
Why no calculator weighs these factors
Each factor above depends on facts, evidence and local law. A calculator could assign arbitrary percentages to “weak evidence” or “disputed liability”, but those numbers would look precise without being grounded in anything. ClaimSettleIQ’s estimator instead shows only arithmetic you control, so you can see exactly where assumptions enter.
Sources and references
- Legal Information Institute: “Comparative negligence” (opens in a new tab) — general description of pure and modified comparative negligence
- Legal Information Institute: “Collateral source rule” (opens in a new tab) — the collateral source rule and the fact that states have modified it
- Legal Information Institute: “Eggshell skull rule” (opens in a new tab) — the rule that a defendant takes the plaintiff as they find them