The federal McCarran-Ferguson Act, 15 USC 1011, contains the basic provisions which give states the power to regulate the insurance industry. This power particularly applies to in the automobile insurance industry, where there is very little federal interest, excepting matters involving interstate commerce in general.

State law dictates not only what form of negligence law applies to automobile accidents but also what form of liability insurance individuals must maintain in order to lawfully operate a motor vehicle. The liability insurance that they purchase generally parallels the form of negligence law found in their particular state.

In general, liability for accidents can be affected by any of the following: