Two hearing-impaired men are accused of two Louisville murders, and now one of the men is testifying against the other.

One man has already pleaded guilty to the two murders, but Justin Murray, who is now on trial, says he is an innocent eyewitness.

Michael Knights, who is deaf, took the stand Tuesday afternoon, but before that his attorney says he had an apparent panic attack and shortness of breath.  EMS was called in, and Knights ended up testifying about twenty minutes later.

Police say he and his deaf friend, Justin Murray, killed 72-year-old Darrel Spencer.  The murder happened in December of 2008 at a downtown Army surplus store.

Investigators say later the two killed Marcus Penny outside his Manslick Road apartment.  Knights says the murder of Penny happened as he was trying to confront Penny about leaving alone a woman he was dating.

Murray's attorney David Mejia asked Knights on Tuesday, "The question is, you and you alone stabbed Marcus Penny, isn't that true?"

Knights replied, "Yes."

Meija:  "WIth the knife you alone possessed?"

"Yes," Knights replied.

Knights later gave conflicting statements on the stand about what happened.  He is serving life in prison without parole for 25 years for the two murders.  If found guilty, Murray could get the death penalty.