½½LOUISVILLE, Ky. (WDRB) -- A blood stain expert called to the stand in the David Camm murder trial says based on his own tests, Kim, Jill, and Brad Camm were shot and were lying at the scene for some time.

The defense has repeatedly said David Camm was playing basketball at the time of the shootings and returned home to discover his family had been shot, then called police.

This expert says when police arrived, Camm's family had already been there at least an hour to an hour and a half beforehand.

Bart Epstein is a blood stain expert who worked for the Minnesota State Crime Lab. He's now retired and helping with private consulting cases. He became involved with the Camm case in 2001.

He is being questioned about blood stain patterns at the home of the Camm family where Kim, Jill, and Brad were killed, as well as the blood on Camm's clothing.

Epstein tells the jury, based on blood at the scene and his own tests, that Kim, Jill, and Brad Camm were shot an hour to an hour and a half before police arrived on scene. That is based on clotting and congealing of the blood.

He also testified that based on the blood found on Camm's clothing, Camm came in contact with his family's blood, but it wasn't spatter. The prosecution has argued it was spatter and that Camm shot his family.

Epstein says the blood on Camm's shoes appeared to be serum blood stains that were transferred after the crime. His conclusion is that this matches up to what David Camm has said.

Camm claims he was playing basketball and returned home to find his family had been shot and killed. But the prosecution has argued evidence could have been cleaned up and that the bodies were moved. Epstein says however, based on blood stain patterns, it appears they weren't.

Blood on Camm's clothing was also discussed. Epstein says he conducted his own tests and says had Camm shot his family, there would have been larger stains on his clothing and not just the small blood stains found. Epstein says blood on Camm's shirt most likely came from Jill's hair when Camm reached into the Bronco to grab his son. He concluded the blood was transferred to Camm's clothes. However, the prosecution claims it was blood spatter that came from Camm killing his family.

Prosecutor Stan Levco says so far this case is going as expected.  He says he never tried a case longer than a month and this trial has exceeded that. He says the jury is handling it well:  "Their stress will come when it's time to deliberate. Right now, it's more difficult for us than them."

This is the second week of testimony for the defender. Levco says this is going the way he expected.  "I think we're looking at the end of October, if I had to guess, but I've been wrong pretty consistently in predicting when it's going to be over."

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