Tape a powerful tool for cops

Two police officers traveled all the way from Chicago to Floridato question their main suspect. He confessed after a few hours in aKey West lock-up, even though he had gotten away with the murder for16 years.

A good defense attorney might already be spinning an argument ofcoercion to get the statement tossed out. Coercion was, in fact,argued at the trial.

But while Billy Rouse sat in silence in a Lake County courtroomtwo years ago, jurors were riveted to a television screen, where thesame Billy Rouse - looking and sounding very uncoerced - said plainlyin his videotaped confession: "I killed my mother."

He got 80 years.

Chicago police, like law …