No criminal case in Maine history has been talked about more than the murder of 12-year-old Sarah Cherry. Twenty-one years ago, a Maine jury convicted Dennis Dechaine of the crime, and a judge sentenced him to life in prison without possibility of parole. Instead of ending the story, however, that just got it going.

Since his conviction, Dechaine has steadfastly maintained his innocence, and so has a group of advocates, beginning with his friends and family, but growing over time to include people who have studied the case and become convinced of his innocence.

The case has been the subject of newspaper and magazine stories, a book, television documentaries and thousands of online postings and letters to the editor of virtually every publication in the state.

But just because every aspect of this case has been discussed at some time or another, it does not follow that it’s always appropriate to look at every aspect all the time. Especially in court, it is right to focus on only the issues that could factor into a decision and not get distracted by the mountains of fact and opinion that have piled up over time.

At issue now is a decision by Superior Court Justice Carl O. Bradford to disallow opinions by two forensic pathologists offered in support of a motion for a new trial based on DNA evidence. The experts reach a different conclusion about the time of Sarah Cherry’s death than the state’s medical examiner, which is a key pillar in Dechaine’s claim of innocence.

But the upcoming hearing is to decide whether Dechaine should get a new trial based on DNA evidence — it is not a new trial itself.

The subject of the hearing should be the male DNA discovered on the victim’s bloodstained fingernail, which did not come from Dechaine.

The proper focus of the hearing should be the DNA itself, how it got there and what it might tell us about the murder. Did the victim scratch her killer while fighting for her life? Were the fingernails contaminated over time? Is there proof that a jury that had seen the DNA would have reached a different verdict?

That’s the important question now, and that’s the one that should be answered by this hearing. Bradford is right to keep the focus where it belongs.