Question:
When is an arrest warrant used?

Answer:
Usually, a warrant is required before you can be taken into custody from within your home. But you can be arrested at home without a warrant if fast action is needed to prevent you from escaping, destroying evidence, endangering someone's life or seriously damaging property.
 
An arrest warrant must be signed by a magistrate or judge, who must have probable cause to believe that you committed a crime. Once an arrest warrant is issued, any law enforcement officer in the state can arrest you-even if the officer does not have a copy of the warrant. Generally there is no time limit on using a warrant to make an arrest.
 
Before entering your home, a law enforcement officer who posesses a warrant, should knock, identify himself or herself and tell you that you're going to be arrested. If you refuse to open the door, or if there's another good reason, the officer can break in through a door or window. If the police have an arrest warrant, you should be allowed to see it. If they don't have the warrant with them, you should be allowed to see it as soon as practical.
 
The police may search the area within your reach. If you are arrested outdoors, they may not search your home or car. Resisting an arrest or detention is a crime. If you resist arrest, you can be charged with a misdemeanor or felony in addition to the crime for which your are being arrested. If you resist, an officer can use force to overcome your resistance or prevent your escape.