Dateline | January 31, 2014
>> narrator: david camm , once an indiana state trooper was now locked up in the floyd county jail, charged with the murder of his wife and children.
>> tell me about your emotions.
>> every time i heard a key jingle outside my door, i would think to myself, oh, this is it, they have figured it out. they're going to come back and say david , we messed up.
>> narrator: sam had the grit to make his voice heard.
>> why did you take on the responsibility, sam, to take it as far as you could?
>> i didn't have any other options. i know he was innocent, i know he's lost his family. and i know he lost hiss freedom. what am i going to do? he hasn't lost me.
>> the focus -- maybe something awful here and david snapped and killed his family.
>> i never thought that david killed his family. never thought it, never did.
>> narrator: kim 's parents, janice and frank were absorbing the awful facts the police told them, that their son-in-law was the killer.
>> they have made an arrest and it's david .
>> i was just out of it. and when it finally did sink in, i was back and forth.
>> we're talking about the early days here.
>> i wasn't 100% sure, i was just going by what the police was telling me.
>> narrator: before long they became convinced that their son-in-law had murdered his family. 15 months after the murders, david camm went on trial, he pleaded not guilty. by now the prosecutor's timeline changed. originally he said that david killed his family between 9:15 and 9:30 after david returned from the basketball game. the defense had shown the time of death was somewhere between 7:30 and 8:00 p.m .
>> everything said this happened much earlier.
>> now the prosecutor argued that david went to the gym at 6:00, then he secretly ducked out of the basketball game, went home killed his family and then returned to play ball. there was a call to a customer from his land line phone, time stamped 7:19 p.m .
>> you've got a husband that says i was playing basketball at 7:00, you've got a phone record that says he likely is making a call to a customer land line in his home, so he's not playing basketball.
>> almost certainly would be the one that was doing it.
>> and this phone call blows up his alibi?
>> narrator: the prosecutor moved on to the crime scene and focused on what happened to kim in the garage that night.
>> we thought that the pants had been pulled down.
>> you have accused the husband of the murder, why are you telling the jury that he was pulling h in ing her panels down.
>> trying to get the jury to think that somebody was in there to molest her.
>> that there had been a break in.
>> narrator: investigators had never located the murder weapon. the only physical evidence the cops had that the gun was in david 's hand that night was this. barely visible drops of blood on the lower left of camm's t-shirt.
>> blow back, this is what happens when you shoot somebody at close range?
>> you get that blood on your shirt.
>> he got high impact spatter on hiss t-shirt, he has to be within four feet of the child at the time that the child was killed.
>> narrator: the prosecution believed david camm shot from inside the car, targeting jill in the back seat. that's how her blood sprayed on his shirt. but why? why would david camm kill his family? the reason for those killings, the prosecutor, declared was that david camm was a philandering husband.
>> it probably was one of the first times that i really ever heard kim cry.
>> remember kim 's old friend, marcy mccloud? the prosecutor had her testify about an affair david had when kim was pregnant in late 1994 . marcie testified that kim called her in tears to say that she and david were separating. marcie soon after visited kim .
>> she was upset. you know, and saddened by it, especially just having a baby.
>> narrator: and there was more. just three weeks before the murders, marcy had another troubling phone call from kim .
>> her demeanor was different, her attitude and she didn't want to hang up the phone, but yet she didn't want to talk.
>> narrator: the old friends made plans for kim a and the children to visit marcy . then kim said something she never explained.
>> she felt like history was repeating itself. we didn't go into what that meant because she said, we'll talk about it when i get there.
>> kim never made it. at trial t clear i, the clear implication was that david was catting around again.
>> there's people he pulls over, flirts with them and eventually seduces them.
>> in court the prosecutor called a parade of women presenting them as david camm 's conquests, more than a dozen of them recounting the fondling, the sex in the patrol car .
>> he wanted to have women and his wife was getting in the way?
>> she was an on stack bstacle for the kind of women he wanted to pursue?
>> narrator: the prosecutor had a capper, something really dreadful. the medical examiner's testimony that the injuries on the murdered daughter, 5-year-old jill were consistent with sexual abuse.
>> not a little girl falling on the monkey bars .
>> no, not the monkey bars , it wasn't a bicycle or anything like that.
>> narrator: so the killer with blow back blood spatter on his t-shirt. the defense lawyers had their work cut out for them.
>> you had an uphill fight as a defense attorney .
>> yes. and that was not unusual, but this was so much more high profile.