Slater, 29, was arrested in August after police were called to a fight at a late-night party in Los Angeles. According to officers, Slater was found swinging his arms and yelling incoherently. He became involved in a fight after a man attempted to stop him from punching his girlfriend, Michelle Jonas. He later told police that he had been taking heroin, cocaine and had been drinking "for a couple days and had only a couple hours of sleep".
The judge in a Los Angeles court issued protective orders for both Michelle Jonas and Julio Flores, the policeman who Slater kicked down a flight of stairs after responding to the emergency call.
Slater's lawyer, Michael Nasatir, said that his willingness to plead no contest - which under California law is the equivalent of a guilty plea - was evidence of "Christian Slater taking responsibility for his actions." Slater has previously been in jail after a drink- driving conviction eight years ago, and in 1994 he was arrested at John F Kennedy airport in New York with a handgun, although it was not loaded.
Yesterday's sentence came only hours after fellow actor Robert Downey Jr was jailed for six months on drugs and firearms charges.
Slater's term is to be followed by three months in a residential drug treatment programme. Ted Goldstein, a spokesman for the city attorney, said the actor must begin his sentence before 10 January and enroll in a year- long programme for batterers.