PORTLAND – More testing of items from the investigation of Sarah Cherry’s murder could help clarify whether the DNA found on one of her thumbnails came from contamination, a witness said Wednesday at a hearing on Dennis Dechaine’s motion for a new trial.

Swabs of certain items from the 1988 kidnapping and murder of the 12-year-old Bowdoin girl have already been tested for male DNA and come up negative. Those items include sticks that were used to assault the girl, the rope that bound her hands and the scarf that was over her mouth.

Witness Rick Staub, the forensics laboratory director of a company in Texas that handled some of the tests, testified that there could be value in doing additional DNA analysis on evidence in the case. If DNA similar to the thumbnail DNA was found on other items, it would make it unlikely that the thumbnail DNA came from contamination during the autopsy.

The partial DNA profile extracted from the girl’s left thumbnail is at the center of Dechaine’s attempt to get another trial. On Wednesday, his lawyer, Steve Peterson, continued to present witnesses’ testimony aimed at convincing Superior Court Justice Carl Bradford that jurors would not have convicted Dechaine in 1989 had they known about the DNA.

One of those witnesses, Rick Staub, said it’s hard to imagine that DNA was transferred to the thumbnail by clippers used in the autopsy — as Deputy Attorney General William Stokes has argued is the most likely scenario — unless the clippers had wet blood on them and were used immediately afterward.

Staub’s lab did a type of testing that looks at the male Y chromosome. The testing is useful when there is an abundance of female DNA and less male DNA, such as in sexual assaults or homicides involving female victims and male perpetrators.

Staub said there was a very low level of male DNA from the thumbnail clipping extract. When testing is done at such low levels, several males are often detected, he said.

“In this particular case, it’s very clear it’s one male” whose DNA is on the thumbnail, he said.

Dechaine has been ruled out as a source of the DNA.

His hearing, which began Tuesday, has involved much technical information about types of DNA testing that have come into use since the late 1980s, as well as testimony about the lack of awareness of DNA evidence at the time and the chain of custody of the nail clipping.

Witnesses have included people who were involved in the case, such as a state police trooper who was present for the autopsy, the jury foreman, the prosecutor and Dechaine’s original trial lawyer.

Dechaine, now 54 and serving a life sentence, has attended the hearing but is not testifying. Also in the courtroom are relatives and family friends of Sarah Cherry and members of Trial and Error, a Dechaine advocacy group.

A witness for the state testified Wednesday about the conditions in which autopsies were done in the late 1980s. Robert Goodrich, a forensic medical technician in the state Medical Examiner’s Office, described “very dirty” conditions.

Autopsies were done in the morgue of the Kennebec Valley Medical Center in Augusta because his office did not have its own facility. Instruments were kept in a metal chest of towel-lined drawers at the hospital, masks were not used, and gloves weren’t worn consistently, he said.

Nail clippers were used repeatedly and may have been rinsed or disinfected between autopsies, Goodrich said. But small instruments, if they weren’t grossly contaminated, might just go back into a drawer, he said.

He said precautions were taken for blood typing at the time, but not for DNA testing.

“I didn’t know anything about it. I didn’t know how it was done and it wasn’t employed in our facility,” he said.

Sarah Cherry was abducted from a baby-sitting job on July 6, 1988. A search for her and Dechaine, then a 30-year-old farmer in Bowdoinham, began after a notebook and a truck repair bill bearing his name were found in the driveway of the home.

Dechaine was seen walking out of the woods about three miles away that day. His pickup truck was found nearby that night. The girl’s body was found two days later, about 450 feet from where Dechaine’s truck had been. The rope binding her hands and the scarf around her mouth and neck were from the truck.

Dechaine said he went into the woods to inject “speed” and was alone and lost. He maintains that someone took the items from his truck.

The hearing on his motion for a new trial will continue today. 

Staff Writer Ann S. Kim can be contacted at 791-6383 or at:

akim@pressherald.com

Twitter: AnnKimPPH