Former State Trooper on Trial for 3rd Time in Family's Slaying

Oct. 1, 2013 — -- David Camm, the former Indiana state trooper accused of killing his wife and two kids, will return to court today, defending himself against murder charges for the third time.

Camm, 49, is charged with shooting to death his wife, their 7-year-old son and 5-year-old daughter in their car in Georgetown, Ind., in 2000. He has consistently denied the allegations.

"It's a double nightmare because I am here for something I didn't do," Camm told CBS affiliate WLKY in July 2012.

Camm has been convicted twice, in 2002 and 2006. He appealed both times, and the convictions were overturned on the grounds that the court allowed inadmissible evidence about Camm's alleged affairs, along with accusations that he molested his daughter.

David Camm Murder Trial: Second Suspect Had Foot Fetish? Find out more here.

In 2005, the DNA on a sweatshirt found at the crime scene was tied to convicted burglar Charles Boney, who was later convicted on three counts of murder and sentenced to 225 years for the deaths.

Camm's lawyers now say that evidence will help their client.

"The judge decided the DNA was admissible and I think that that's a big deal," Richard Kammen, attorney for David Camm, told ABC News.

Even after Boney's conviction, prosecutors have refused to "admit even the possibility that a serious mistake had been made," Camm's lawyers told ABC News.

Prosecutors dispute that, saying Boney knew Camm and sold him a gun, and they called DNA experts to the stand last week to testify that Camm is linked to the slayings by tiny droplets of his wife's blood on his shirt, a fine mist they say could only be spatter from a gunshot.

The defense argues that the blood was transferred onto Camm's clothing when he pulled his son out of the car to resuscitate him.

"You just continue to persecute me night on and night in and if it's because I gave my son CPR, then so be it," Camm said while being interrogated in 2000.

The defense is expected to open its case later today by calling the 11 men with whom Camm says he was playing basketball at the time of the slayings.

"He's hoping that this time there'll be a fair trial," Kammen said.

Camm has once again pleaded not guilty. Meanwhile, hundreds of people have signed a petition on the website Change.org to free David Camm.