[JURIST] The US Court of Appeals for the Ninth Circuit [official website] ruled [PDF opinion] Thursday to strike down a California law making it a criminal offense for individuals to knowingly make false accusations against police officers. The law, which carried a potential jail sentence of up to six months for guilty parties, was implemented in 1995 after the 1991 taped beating of Rodney King [BBC backgrounder] prompted a barrage of hostile complaints against the police. The appeals court, however, determined that the law was an unconstitutional infringement on speech since false statements supporting officers were not also made unlawful:

a formal complaint of peace officer misconduct triggers a mandatory investigation conducted by the peace officer’s employing agency. Within the limited context of that investigation, section 148.6 criminalizes knowingly false speech critical of peace officer conduct, but leaves unregulated knowingly false speech supportive of peace officer conduct. Because we conclude that the statute impermissibly discriminates on the basis of a speaker’s viewpoint in violation of the First Amendment, we reverse the district court and grant the petition.

The challenge to the law was made by a Beverly Hills man who was convicted in 1999 for falsely complaining about a police officer. The American Civil Liberties Union [advocacy website] praised the court's decision [press release], but California prosecutors expressed disappointment and said they may appeal to the US Supreme Court. AP has more.