Accidents are a broad category of incidents that may result in personal injuries or property damage. Personal injury refers to an injury to a person’s body—also known as bodily injury—or to their mind or emotional well-being—also referred to as emotional distress or pain and suffering. Property damage refers to damage to any kind of real property (real estate) or personal property (all property that is not real estate).

Accidents usually refer to incidents caused by someone else’s negligence rather than by their intentional act. Claims for personal injuries or property damage resulting from an accident or negligent act of another person or entity may create legal liability if the person injured in the accident can prove another person or entity breached their duty of ordinary care in the activity that led to the accident (driving a motor vehicle, for example) and that negligence or breach of the duty of ordinary care caused personal injuries or property damage to the claimant.

Legal claims for personal injuries and property damage resulting from accidents are primarily a matter of state law and may be located (1) in the state’s court opinions—also known as cases, case law, or common law—such as for the elements of a negligence claim; or (2) in the state’s statutes when the state legislature has defined a certain type of claim or recovery for personal injury or property damages caused by a certain type of negligent act or negligent person or entity—such as an accident caused by the negligence of a governmental official or entity.

In California, accidents that cause personal injuries or property damage due to someone else's negligence can lead to legal liability. To establish a claim, the injured party must demonstrate that the other person or entity had a duty of care, breached that duty, and that the breach directly caused the injuries or damages. California's negligence laws are derived from both statutory law and case law. Statutory law may outline specific claims or recovery methods, especially in cases involving government entities, while case law provides precedents for the elements of a negligence claim. For instance, in a car accident, the injured party must show that the driver who caused the accident failed to exercise reasonable care while driving. If successful, the injured party may be entitled to compensation for medical expenses, lost wages, pain and suffering, and other damages. It's important to note that California follows a comparative negligence rule, which means that if the injured party is found to be partially at fault, their compensation may be reduced proportionally.