POLICE officers secretly filmed for a TV documentary which revealed them watching porn on duty and treating rape allegations lightly, could be disciplined, their chief constable said today.

Reporter Nina Hobson rejoined the police service last year to go undercover at Leicestershire Constabulary for a Channel 4 Dispatches programme to be broadcast this evening.

Her hidden camera footage reveals a culture of male chauvinism, she said, in which colleagues fail to believe rape allegations, watch porn films on night shifts and make sexist comments.

Ms Hobson said the four-month investigation also exposed derelictions of duty, including officers on patrol playing "hide-and-seek" in their cars and fetching takeaways while pretending to be busy.

Leicestershire Chief Constable Matt Baggott watched a "rough cut" of the documentary last night and today apologised for the bad behaviour caught on camera.

He said: "The footage contained examples of incidents ranging from poor behaviour to unacceptable attitudes."

Dispatches: Undercover Copper will be shown on Channel 4 at 9pm.