Cox said he won't be put back by the accusations.

?It?s not a surprise, absolutely not a surprise. I?m a big boy, I?m a Marine, I can?t take some shots. And at the end of the day, I?ll let the people decide,? Cox said. "I think people know that I can stand up. I?m a 21-year prosecutor and I?ve had cops that have stood up for me, and I?m pretty confident that ,at the end of the day, people will make the right choice."

T. Berry, a former Detroit Police lieutenant who investigated the Greene homicide case, said he agrees with Cox.

?I think it?s ludicrous. I think it's phony baloney," he said.

Witness Has Criminal Background

Kay, 35, has a checkered criminal history.

Watch:

1996: He pleaded guilty in Oakland County for breaking and entering and weapons charges.

1997: He was found guilty in Wayne County for attempted arson.

2001: He was found guilty of a weapons charge and possessing marijuana.

Local 4 has learned the Detroit Police Department arrested the witness multiple times between 1997 and 2004.

In June 2004, Kay was arrested on a felony warrant during a traffic stop and was taken back to the 12th precinct, where he, according to police "acted like he fainted" and was transported to the hospital.

Four months later, he filed a report saying police kicked him, broke his fingers, dragged him to a scout car and brought him to the hospital and when he woke up, he was back in his prison cell.

If it's found that Kay gave false testimony while under oath, he could face up to two years in prison.

Several attempts to contact Kay at his Dearborn house were unanswered. Dearborn police confirm that Kay had filed a request for police protection.

Cox's office also issued a statement Tuesday questioning prior testimony given by retired police dispatcher Sandra Cardenas, who claimed she dispatched police cars to a disturbance at the mayor's mansion in 2002.

"Eight years later, in the last hours before an election, again here comes (sic) more unsubstantiated claims," the statement reads. "In fact, a judge tossed out her testimony because she couldn't remember if she remembered. Ms. Cardenas repeatedly failed to name a single person who supposedly told her this information and could not name a single date. Even Gary Brown says all this last minute information is not true."