The Associated Press - The Los Angeles police union filed a lawsuit Wednesday claiming the Police Department ignored its own policy and state employment safety laws when officers were told not to wear helmets while on duty at a protest rally.

Police commanders issued the instructions because they feared the headgear might increase tensions with demonstrators, according to the Police Protective League.

Officers could not access their helmets as the Jan. 10 demonstration in Westwood grew violent, and one officer was hospitalized with a head injury after being hit with a protest sign, the league said.

The suit, filed in Los Angeles County Superior Court, seeks an order preventing the city from barring helmet use. "The LAPD's own emergency operations guide clearly states: 'Do not assign officers without helmets, vests and batons to crowd control missions,'" League President Paul M. Weber said in a statement.

The officers were assigned to a protest over the Israeli invasion of Gaza. Police spokeswoman Officer April Harding said the department doesn't comment on pending lawsuits.

The lawsuit follows a class-action grievance the league filed against the department last month, in which it made similar allegations that officer safety had been ignored. City Council members Dennis Zine and Bill Rosendahl have asked the Police Department to report on its policies related to preparing and equipping officers assigned to crowd control, including helmet use.