When a motorist breaches their duty of care and causes damage, what have they committed?

A motorist who breaches their duty of care, resulting in damage to another party, has committed a tort. In the context of law, a tort refers to a wrongful act or an infringement of a right (other than under contract) leading to civil legal liability. A motorist's duty of care typically includes the responsibility to operate their vehicle safely and considerately to avoid causing harm to others.

When this duty is breached—for example, through reckless driving or ignoring traffic laws—and damage or injury occurs, it establishes the basis for a tort claim. The injured party can pursue legal action to seek compensation for their damages due to the motorist's negligence.

Though negligence is indeed related to this scenario, it is a specific form of tort law. While both negligence and tort involve a breach of duty, tort encompasses a broader range of civil wrongs. The choice of tort as the answer appropriately captures the legal context of the situation described.