AUGUSTA -- A lawyer for convicted child murderer Dennis Dechaine plans to file papers today in Superior Court seeking another trial so he can introduce new DNA evidence.

Attorney Steve Peterson said he plans to file a motion in Rockland asking for a new trial based on DNA testing that was done and any new testing the court would be asked to authorize.

Dechaine, formerly of Bowdoinham, is serving a life sentence for the 1988 murder and rape of 12-year-old Sarah Cherry, who was abducted while baby-sitting in her hometown of Bowdoin. Dechaine supporters say he was wrongly convicted and have been pressing for a new trial.

A new post-conviction statute in Maine allows prisoners who want to introduce DNA evidence that they think could exonerate them to do so by Monday.

Dechaine's attorneys previously asked for a new trial using DNA evidence found under the young victim's fingernails after Dechaine was convicted. Even though testing shows that the DNA belongs to someone other than Dechaine, the request was turned down.

With a change in the law in 2006, prisoners can seek new trials based on technological advances in testing.

"Under the old statute, for all practical purposes we not only had to establish that it was not Dechaine's DNA under the fingernail clippings but we had to -- by clear and convincing evidence -- show that it was the DNA of the actual perpetrator which was a burden practically impossible to meet," Peterson said.

Now, a new trial would be ordered if, after reviewing all the evidence in a case, a judge concludes that the DNA evidence would make it probable that a new trial would lead to a different verdict.

Peterson said he's hoping to use advances in so-called "touch DNA," which could open the way for examination of Sarah Cherry's clothes. Older methods of DNA analysis relied on secretions, hair and fluids.

Deputy Attorney General Bill Stokes said he had not seen Peterson's petition.

"Obviously, what we'll do is we'll follow the statute, we'll file a response and we anticipate that we'll have a hearing before the Superior Court in due course," Stokes said.

James Moore, a retired agent with the Bureau of Alcohol, Tobacco and Firearms who has researched the Dechaine case and written two books on the subject, said he welcomes the new motion but is skeptical that a judge will allow any evidence that would shed light on the identity of a new suspect.

Moore's books have fueled suspicion among a wide circle of Dechaine supporters that he was unfairly convicted.

Police found Cherry's body in the woods in Bowdoin in July 1988, about 400 feet from where Dechaine's pickup truck was found parked the night of her disappearance.

Dechaine, who lived in the next town over, was questioned by police after walking out of the woods that night. He said he'd gotten lost while fishing, but he later admitted he'd been injecting amphetamines.

A car-repair bill and notebook belonging to Dechaine were found in the driveway of the home from which Cherry had disappeared. The rope that bound the girl was of the same material as rope found in the back of Dechaine's truck. Police said Dechaine confessed to the murder, but he insists that his words were twisted.

Moore noted how some officers' field notes about what Dechaine said differed from their testimony, which he said was much more incriminating. He also said the original estimate on Cherry's time of death was that it occurred after Dechaine was already in custody.

To answer criticisms about the prosecution of the case, state Attorney General Steve Rowe created a commission in 2004 to investigate allegations that prosecutors and police officers altered notes, misled the jury, ignored alternative suspects and destroyed evidence before, during and after Dechaine's trial in 1989.

The volunteer commission said it found no evidence of misconduct, but their four-page report was not accompanied by any documents, notes or other evidence.

Moore's court challenge to get commission records was rejected by the Maine Supreme Judicial Court.

The Cherry family and friends have said that each effort by Dechaine to get a new trial aggravates the painful memories of the girl's death and makes it harder to move on.