Most often, the term warrant refers to a specific type of authorization; a writ issued by a competent officer, usually a judge or magistrate, which permits an otherwise illegal act that would violate individual rights and affords the person executing the writ protection from damages if the act is performed.

A warrant is usually issued by a court and is directed to a sheriff, constable or a police officer. Warrants normally issued by a court include search warrants, arrest warrants, and execution warrants. A typical arrest warrant in the United States will take the approximate form of: "This Court orders the Sheriff or Constable to find the named person, wherever he may be found, and deliver said person to the custody of the Court."

Warrants are also issued by other government entities, particularly legislatures, since most have the power to compel the attendance of their members. This is called a call of the house.

In the United Kingdom, senior public appointments are made by warrant under the Royal sign-manual, the personal signature of the monarch, on the recommendation of the government. In an interesting survival from medieval times, these warrants abate (lose their force) on the death of the sovereign if they have not already been executed. This particularly applied to death warrants in the days when England authorized capital punishment. Perhaps the most celebrated example of this occurred on 17 November 1558 when several Protestant heretics were tied to their stakes in Smithfield, and the firewood bundles were about to be lit when a royal messenger rode up to announce that Queen Mary had died and that the warrants had lost their force. The first formal act of Mary's successor, Elizabeth I, was to decline to re-issue the warrants, and the heretics were released a few weeks later.

Warrant has several meanings:

The Law is a system of rules and guidelines which are enforced through social institutions to govern behavior. Laws are made by governments, specifically by their legislatures. The formation of laws themselves may be influenced by a constitution (written or unwritten) and the rights encoded therein. The law shapes politics, economics and society in countless ways and serves as a social mediator of relations between people.

A general distinction can be made between civil law jurisdictions (including Canon and Socialist law), in which the legislature or other central body codifies and consolidates their laws and common law systems (including Sharia), where judge-made binding precedents are accepted. In some countries, religion may inform the law; for example, in jurisdictions that practice Islamic law, Jewish law or Canon law.

The adjudication of the law is generally divided into two main areas. Criminal law deals with conduct that is designated dishonest by the government and in which the guilty party may be imprisioned or fined. Civil law (not to be confused with civil law jurisdictions above) deals with disputes between individuals or organizations, in which compensation may be awarded to the wronged litigant.