The police, in every Grand Theft Auto game, play a major role both in and out of missions. When outside missions, players will often see police officers walking around the streets, and patrolling in their cars, and these officers will do whatever it takes to stop criminals, so when the player commits a crime, the officers will not rest until they have taken him out or they have lost him. They also play a large part in missions too, where they often try to stop the player from being able to carry out their task, such as in Grand Theft Auto IV when the NOOSE try to stop Niko from escaping from an old abandoned building.
 Wanted Level System
In each Grand Theft Auto game, the police will come after you for committing serious crimes, such as hit and run, or carjacking. They all work on a principal of a system of a star level system, ranging from 0 stars to 6. When the player has zero stars, the police will not come after him, however when they commit a crime and the police are aware, then the wanted level will be bumped up. As the number of crimes committed by the player increases, the wanted level will increase and the police will try harder to catch them, with officers on foot coming at first, then the FBI and US Army coming later on. There are also a few of ways of decreasing a wanted level, including police bribes and visiting Pay N' Spray.
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