DAVENPORT, Iowa (KWWL) - Jerry Burns' lawyers called only one person to the stand Thursday while defending their client on murder charges.
Dr. Michael Spence, who said in court Thursday he'd consulted on over 1,000 cases with forensic evidence, talked about "dry transfer" of DNA in Michelle Martinko's murder case.
Spence testified packaging evidence together in this case awarded a chance for DNA to be transferred between items, potentially corrupting evidence state prosecutors had been leaning on.
"I think that you need to separate out the items as early as you possibly can. I can understand why law enforcement officers in 1979 might not have thought of that," Spence said.
Crime scene pathologist Linda Sawer testified last Friday for the prosecution, in part saying evidence cannot transfer DNA once dried.
"I disagree with that completely," Spence said on the witness stand Friday.
During cross-examination, State Prosecutor Nick Maybanks asked Spence if it wasn't through murdering her, how else did Jerry Burns' DNA end up on the back of Michelle Martinko's dress.
"I don't believe the transfer did happen and I don't believe the transfer didn't happen. It's impossible to tell from the snapshot," Spense responded, admitting it was only in the realm of possibilities.
Court adjourned early for the second day in a row Thursday. The parties will regroup Friday morning where the state has an opportunity to present counter-evidence to the defense's case.