Everytime the player kills a police officer or bombs a business, the Heat Level is increased. It ranges from 0 to 5. If it is above 1 police will attack you. When it gets to 5 police will shoot and will even hit you with their patrols. To avoid this the player can bribe police agents if his heat is less or equal than 2. This will assure their cooperation for a limited time. They will even help the player against the mobsters. After that time their protection is meaningless.