Casualty insurance is the branch of insurance that protects people and businesses against legal liability—the responsibility to pay for harm they cause to others. Before you can understand any liability policy, you need to understand why someone becomes legally obligated to pay in the first place. This guide walks you through the legal building blocks—negligence, torts, damages, and defenses—in plain language so the rest of your casualty studies click into place.

What "liability" really means

Legal liability is a legally enforceable obligation to pay for the harm you cause another person or their property. Liability insurance does not pay because you feel bad or because the other person is hurt—it pays because the law says you are responsible. That distinction matters: a liability policy responds when the insured is legally obligated to pay damages, not simply when an accident happens.

Liability can arise three ways:

• By tort – a civil (non-criminal) wrong against another person, which is the focus of almost all casualty insurance.
• By contract – obligations you voluntarily take on, such as a "hold harmless" agreement.
• By statute – liability the law imposes regardless of fault, such as workers compensation.

Torts: the source of most liability claims

A tort is a civil wrong (other than a breach of contract) that causes injury or damage, for which the law allows the injured party to seek money damages. Torts fall into three categories, and exam questions love to test the differences.

1. Intentional torts

An intentional tort is a deliberate act that causes harm—assault, battery, libel, slander, false arrest, or invasion of privacy. The person meant to do the act (even if they did not mean to cause the full extent of the harm). Standard liability policies often limit or exclude intentional acts, which is an important exam theme.

2. Negligence

Negligence is the failure to use the degree of care that a reasonable, prudent person would use under similar circumstances. It is unintentional—the person did not mean to cause harm but fell short of the expected standard of care. The overwhelming majority of liability claims are negligence claims, so master this one.

3. Strict liability (absolute liability)

Strict liability holds a party responsible for damages regardless of fault or intent. It applies to inherently dangerous activities (blasting, keeping wild animals) and to product manufacturers under product liability law. The injured party does not have to prove carelessness—only that the activity or product caused harm.

The four elements of negligence

To win a negligence claim, the injured party (the plaintiff) must prove all four of these elements. If even one is missing, there is no negligence. A favorite memory aid is the "four Ds," but the classic wording is:

1. Duty of care – The defendant owed a legal duty to act reasonably toward the plaintiff.
2. Breach of duty – The defendant failed to meet that duty (did something a careful person wouldn't, or failed to do something a careful person would).
3. Proximate cause – The breach was the direct, unbroken cause of the harm. "Proximate" means the injury was a reasonably foreseeable result of the breach.
4. Damages – The plaintiff suffered actual, measurable harm (injury or loss).

Exam tip: Duty → Breach → Causation → Damages. If a question describes an accident but no actual injury or loss occurred, the negligence claim fails on the damages element.

Types of damages

When liability is established, the responsible party owes damages—money to compensate or punish.

• Compensatory damages make the injured party "whole." They split into special damages (specific dollar amounts like bills and lost income) and general damages (harder-to-measure harm like pain and suffering).
• Punitive damages are meant to punish, not compensate. They apply only to especially bad conduct. Many policies and some states restrict whether insurance can pay punitive damages—watch for this on exams.

Bodily injury vs. property damage

Liability policies almost always separate the two main kinds of harm:

• Bodily injury (BI) – Physical injury to a person, including sickness, disease, and resulting death. Some policies extend BI to mental anguish that accompanies physical injury.
• Property damage (PD) – Physical injury to or destruction of tangible property, including loss of use of that property. Note "tangible"—pure economic loss without physical damage usually isn't PD.

Remembering that BI = harm to people and PD = harm to things helps you decode coverage triggers throughout casualty insurance.

Defenses to negligence

Even when an accident occurs, a defendant can reduce or eliminate liability using recognized defenses. These come up constantly on exams.

Comparative negligence

Under comparative negligence, an injured party's recovery is reduced by their own percentage of fault. If a plaintiff is found 30% at fault, they collect 70% of the damages. Most states use some form of comparative negligence today.

Contributory negligence

Under the stricter contributory negligence rule, if the injured party contributed to any degree (even 1%) to their own injury, they may recover nothing. Only a few states still follow this harsh rule, but it's a classic exam contrast with comparative negligence.

Assumption of risk

Assumption of risk is a defense arguing that the injured party knowingly and voluntarily accepted the danger of an activity (for example, a spectator hit by a foul ball at a baseball game). If you accepted a known risk, you generally cannot recover for harm from that risk.

Other common defenses

• Last clear chance – Even a negligent plaintiff may recover if the defendant had the final opportunity to avoid the accident and didn't.
• Intervening cause – A separate event that breaks the chain of causation may relieve the original party of liability.

Vicarious liability

Vicarious liability means being held responsible for the negligent acts of another person. The classic example is an employer being liable for the actions of an employee acting within the scope of their job (the legal doctrine of respondeat superior—"let the master answer"). Other examples include a parent being responsible for a child or a car owner being liable for a permissive driver. Vicarious liability is why commercial liability policies are so important: a business can be sued for what its workers do.

Key terms at a glance

• Tort – A civil wrong (not a crime, not a contract breach) allowing money damages.
• Negligence – Failure to use reasonable care; unintentional.
• Standard of care – What a reasonable, prudent person would do.
• Proximate cause – The direct, foreseeable cause of harm.
• Liable – Legally responsible to pay.
• Plaintiff / Defendant – The party suing / the party being sued.
• Damages – Money awarded for harm (compensatory or punitive).

Common exam traps

• Negligence requires all four elements. A breach with no actual damages = no negligence claim.
• Contributory vs. comparative. Contributory can bar recovery entirely for any fault; comparative merely reduces it. Don't swap these.
• Strict liability needs no proof of fault. If a question stresses "dangerous activity" or "defective product," think strict/absolute liability.
• Punitive damages punish; compensatory damages reimburse. Special damages are the specific dollar losses; general damages are pain and suffering.
• Property damage must be to tangible property and includes loss of use. Pure financial loss usually isn't PD.
• Intentional acts are usually excluded from standard liability coverage—insurance is built for accidental (negligent) harm.

Quick recap

• Casualty insurance covers legal liability—the legal duty to pay for harm you cause others.
• Liability arises through torts, contracts, or statutes; torts are intentional, negligence, or strict liability.
• Negligence has four elements: duty, breach, proximate cause, and damages—all must be present.
• Damages are compensatory (special + general) or punitive; only compensatory damages make the victim whole.
• Bodily injury = harm to people; property damage = harm to tangible property, including loss of use.
• Key defenses include comparative and contributory negligence and assumption of risk.
• Vicarious liability makes one party responsible for another's negligence—central to commercial coverage.