Expert testifies about audiotapes in Simpson trial

A Las Vegas police detective said today he didn't believe O.J. Simpson was involved in a robbery when he first received the call.

"It didn't make sense," said detective Andy Caldwell, the lead investigator.

Caldwell went on to describe how he eventually saw Palace Station security video showing Simpson at the hotel.

He said police had enough information to arrest Simpson that night.

"If it was anybody else we would have arrested him that night," he said. "But because of who he was, we wanted to make sure we had everything right with our investigation."

Today was the third day jurors have listened to testimony in Simpson’s case. Jurors previously heard testimony from Bruce Fromong, one of the two sports memorabilia dealers Simpson and several other men are alleged to have robbed at gunpoint at Palace Station in September 2007.

Simpson, a Heisman Trophy winner and former NFL player, and his co-defendant, Clarence Stewart, have pleaded not guilty to kidnapping and robbery charges.