A warrant and subpoena have some similarities. For instance, they are legal documents involving legally ordering a person to comply with a court order. The documents, however, aren't used in that same way. For instance a type of warrant called a "search warrant" allows a law enforcement officer to search you and/or your premises. Nevertheless, the search is based on probable cause that you may be in possession of evidence involved in a crime.
A warrant and subpoena involve court proceedings. A subpoena, for example, involves a court officer such as a magistrate, judge or clerk of court ordering an individual to appear in court. Typically, the subpoena, or order, requires a person to testify in a court hearing or produce documents on a certain day of trial.
A warrant, however, differs from a subpoena, because it doesn't require an individual to appear in court to testify. Instead a warrant consists of a court official authorising a law enforcement officer to arrest and bring an individual to court to appear before a judge. Unlike a subpoena, a warrant indicates that you may have committed a crime.
Subpoenas are of two types. A general subpoena requires a person to testify in court. A subpoena duces tecum, however, requires an individual bring requested items to court in addition to testifying in court. For instance, if you receive a subpoena duces tecum for a contract in your possession, you must comply and hand over the document to the court.
A warrant comprises three types: search warrant, warrant and bench warrant. Generally, a warrant is issued when a person is charged with a crime. If you don't show up to court for sentencing --- after being convicted of a crime --- or owe money such as a fine, a judge may issue a warrant. Another type of warrant involves a bench warrant. A bench warrant is a court order permitting an individual's arrest for failing to appear in court. For instance, if you receive a subpoena to testify in court but fail to appear, a judge can issue a bench warrant for your arrest. The difference between a warrant and a bench warrant entails a judge issuing the warrant during court proceedings.
Another difference between a subpoena and a warrant involves compensation. A person subpoenaed to testify in a trial who lives a minimum distance from the lawsuit can receive compensation for travel expenses. For instance, if you live in Detroit, but receive a subpoena to testify in Ohio, you may receive money to cover your travel expenses.