In Locke's writings on natural law, the "executive" power was said to relate to the legitimate power of every individual to secure his own rights, while respecting the equal rights of others. In nature, every one can make the judgement that another's actions are aggressive and use physical force to protect his personal rights against trespass/injury. The "police power" of government is the institutionalization of this physical power in the form of a civil government. Under the Lockean social compact, individuals compacted to lay aside their natural right to use personal force against such trespass/injury, in exchange for "civil rights" as a more effective form of protection.

Relating back to the Viking and Saxon "customary" legal systems underlying English common law, laws were framed in terms of "injuries" to the rights of others, valued as:

Trial and judgement were rendered by a tribunal of chiefs or an manorial assembly - the predecessor of the jury. Each injury was compensable through the award of monetary damages determined by the social rank of the parties and the severity of the injury.

The concept of redress to the formalized law for punishment against acts of aggression was embodied in the common law concept of the remedy of "trespass." The organic concept of trespass presumed an act of force or violence, the immediate consequences of which must have caused an injury. Trespass was originally considered to apply only to cases of immediate injury to personal liberty, security and physical property. Eventually, the concept of trespass also evolved to include aggression or encroachment of an injurious nature upon the relative rights of persons.

Although the common law concept of trespass specifically precluded injuries to health, reputation and noncorporeal property, a second type of trespass known as "trespass on the case" evolved in Chancery as a writ to redress nonforcible acts or acts where the damage sustained was a remote or indirect consequence of the act.

By the eighteenth century, any voluntary act that resulted in direct injury to persons or property, whether willful or accidental, fell under "trespass." Whoever caused the harm was liable. Under "trespass on the case," fault through negligence was prerequisite for liability. In 1850, the Massachusetts case of Brown v. Kendall established that for any action in trespass, the act causing injury had to be either intentional or negligently done to establish liability.