Antonio (left) and Alice Balcer can be seen in this undated photo. Credit: Exiles Motorcycle Club

A judge will decide this week whether to try a Winthrop teenager accused of fatally stabbing his parents last Halloween as an adult in a hearing expected to reveal a possible motive and additional details about the crime.

Andrew Balcer, now 18, is charged with two counts of murder in the deaths of Antonio and Alice Balcer, both 47, in their home in the early morning hours of Oct. 31, 2016.

Balcer turned 18 in December, about six weeks after his parents died.

The Maine attorney general’s office, which prosecutes homicides in Maine, wants Balcer tried as an adult. His defense attorney, Walter McKee of Augusta, opposes the motion.

If found guilty of murder as a juvenile, Balcer could be confined to a juvenile facility until he turns 21. He would face between 25 years and life in prison if convicted of murder as an adult.

Balcer called 911 at 1:42 a.m. on the morning of the murders, allegedly telling a dispatcher he “killed his mom, dad and his dog.”

When police arrived about 1:54 a.m., Balcer came out of the house and surrendered without incident but asked them to make sure his brother was OK, according to court documents.

Police found his father in the kitchen, lying on his back in a large pool of blood, according to the affidavit. A Ka-Bar-style knife was found stuck in the floor near his body and a handgun was found on the kitchen counter.

His mother was in a rear bedroom, face down and stabbed in the back.

Antonio Balcer had 13 stab wounds to his chest and torso, according to Deputy Medical Examiner Dr. Clare Bryce. Autopsy results for Alice Balcer have not been released.

McKee said the hearing, scheduled for Wednesday and Thursday at the Capital Judicial Center in Augusta, would make public previously unreleased information about the case.

“There is no question that this was a terrible tragedy,” he said Friday. “What remains to be seen — and which will be the subject of the hearing — is just what happened that night and why it happened.”

The attorney general’s office declined to comment.

Among those expected to testify at the hearing are Winthrop police officers and Maine State Police detectives, who spoke with Balcer on Oct. 31, employees at Long Creek Youth Development Center, where Balcer has been held since his arrest, and psychologists who evaluated his mental state.

Maine law requires a district court judge to consider three factors in deciding whether to try juveniles charged with felonies as adults: the seriousness of the crime; the characteristics of the juvenile, including age, maturity and criminal history; and the sentencing alternatives available to the juvenile court.

Judges in other juvenile murder cases have given weight to how the crimes were committed, the intent of the defendants, and how close they were to legal adulthood.

If the judge finds Balcer should be tried as an adult, the case would be presented to the Kennebec County grand jury. If the grand jury indicted him, an arraignment date would be set and the case would move forward toward a trial.

If Balcer is tried as a juvenile, the case would move to a trial before a district court judge, without a jury.