Proponents of pursuit driving suggest that the consequences of apprehensions resulting from pursuits are worth risks involved, while opponents feel that pursuits are extremely dangerous to the police, the offender, and the bystander. Both criminal and civil law regulate police pursuits, and these laws differ significantly among States. The legal theory underlying many pursuit-related lawsuits is that of negligence. These suits focus on the reasonable care that must be taken by an officer and are based on the duty owed by the officer to the injured party not to engage in certain conduct, the fact that the officer's actions violated that duty, the fact that a negligent breach of duty was the proximate cause of the injury, and that the injured party suffered actual and preventable damage. Unfortunately, the definitions of reasonable care and proximate cause have eluded precise and accurate measurement. Factors usually considered in liability of the parties include the purpose of the pursuit, use of excessive speed, use of warning signals, and police disregard of traffic signals. The law places a strict burden on all officers to operate their emergency vehicles with due regard for the safety of others. 52 footnotes.