The Los Angeles County sheriff yesterday canceled Robert Blake's interview with ABC's Diane Sawyer, killing the jailhouse chat that cost the troubled actor his lawyer.

Blake, accused of murdering his wife Bonny Lee Bakley last year, had agreed to talk to Sawyer on Friday but jailers yesterday told ABC it could not bring microphones and cameras into the jail.

"In keeping with longstanding policy -- barring any unusual circumstances -- to not allow television interviews of Los Angeles County jail inmates in ongoing criminal cases, a televised interview of Robert Blake will not happen," L.A. County Sheriff Lee Baca said in a prepared statement.

The order does not prevent Blake from giving interviews -- he has already done several -- but he cannot appear on camera.

Blake's criminal defense lawyer Harland Braun quit Monday over the proposed Sawyer interview. Braun resigned the case in a letter to Judge Lloyd Nash. The judge still has to formally dismiss Braun as Blake's lawyer.

The defense lawyer said there's no way he can continue representing the former Barretta star.

Braun said he still believes in Blake's innocence, but fears the interview-happy actor might be talking his way into a conviction.

"We have a public who has an open mind to judge this case," Braun said. "If Robert goes on TV, he might damage that . . . by creating a false impression.

"Even if the sheriff doesn't allow the interview this week, he's going to have that need and as soon as he's out on bail," the lawyer said. "He's going to want to be on camera telling his side and that's not going to change."

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