Bite marks on a murder victim's body twice lead to Ray Krone's conviction - but the DNA evidence tells another story.

In Philadelphia, the brazen killing of a state's witness leads police to an alleged hitman - but could the evidence against him be nothing more than smoke and mirrors?

In Texas, a 17-year-old with a violent past is named the killer in a drug deal gone wrong - but a misidentified bullet could unravel the case.

In Louisiana, a disabled teenager is sentenced to death - but the discovery of hidden eyewitness interviews casts new light on his confession.

Did Daniel Dougherty commit murder by arson - or did the fire science used to convict him get it wrong?

There's no doubt Terry Williams committed murder - but what drove him to kill?

After a Delaware store clerk is murdered, a local drug dealer confesses to the crime..but can what he says on tape be believed?

A former trouble-maker sits on Ohio death row for killing an elderly couple, while a desperate team of journalists, attorneys, and former law enforcement make the case of his innocence.