The Rodney King beating led to the 1993 LA riots

Numerous criminal cases have been overturned because of alleged police misconduct and in a trial known as the the Rampart case five officers are facing charges.

The LAPD says it has uncovered proof that some of its officers were involved in shootings, beatings, drug dealing, planting of evidence, false arrests, witness intimidation and perjury.

The latest lawsuit is not specifically linked to the Rampart case but the plaintiffs allege that a "code of silence" led to the scandal.

Hundreds may sue

A Los Angeles lawyer, Bradley Gage, said 300 to 500 officers could eventually join the new lawsuit if it is certified as a class action.

The plaintiffs allege that officers who reported misconduct were taunted by superiors with remarks such as "you better watch your back" and "I will demote you and then I will fire you".

The LAPD also used a pattern of harassment in which managers passed on confidential information about officers being transferred, the suit says.

It's this code of silence that's created out of fear that can lead to corruption within a department

LA lawyer Bradley Gage

There are also allegations of discrimination on grounds of gender, race, disability or age.

About half the plaintiffs are still officers.

"When the police officers are more afraid of the administration than they are of the bad guys out there, then they have to be careful, they can't say anything," Mr Gage was quoted as saying.

"It's this code of silence that's created out of fear that can lead to corruption within a department."

The LAPD's reputation still has not recovered from the videotaped beating of black motorist Rodney King, which led to the 1992 LA riots.