A 22-year-old Rockport man is expected to be arraigned in Massachusetts next week on murder charges in the slayings of his mother, grandparents and the grandparents’ caretaker.

Orion Krause was indicted last week by a Middlesex County grand jury on four counts of first-degree murder, according to Meghan Kelly, communications director for the Middlesex County district attorney.

A conviction for first-degree murder carries a mandatory sentence of life in prison, Kelly said.

Krause has been held in jail since his arrest Sept. 8 in connection with the killings of his 60-year-old mother, Elizabeth “Buffy” Krause; her parents, Frank Darby Lackey III, 89, and Elizabeth Lackey, 85, both of Common Street in Groton, Mass.; and the grandparents’ caretaker, Bertha Mae Parker, 68, also of Groton.

According to police reports, Krause confessed to police that he killed his family with a baseball bat and said he “freed” them.

A judge ruled in October that Krause was competent to stand trial.

Krause’s family and others were increasingly concerned about his state of mind in the days and hours before the killings, and had notified police.

Elizabeth Lackey Krause remembered during a vigil in September. Staff photo by Derek Davis

Documents filed in court last year detailed that his mother had called police the night before the killings, concerned about whether he might harm himself, according to transcripts of her call. She made the call at 9:41 p.m. Sept. 7 from her home in Rockport.

In that call, Elizabeth Krause said her son had been troubled.

She later told the dispatcher that her son was a “very mild soul” and that there were no drugs involved.

Police said Orion Krause later called his mother and said he was in Boston and needed a ride home. Police have not said what happened to the car he had been driving.

When his mother picked him up, she took him to her parents’ home in Groton, located about 40 miles northwest of Boston.

The next day, an hour before police would discover the four bodies, police were alerted that Krause had called a professor at Oberlin Conservatory in Oberlin, Ohio, and said he planned to kill his mother.

The wife of Oberlin College professor Jamey Haddad told police that “Krause stated to Haddad that he ‘had done something bad,’ and had stolen some money and his mother’s car,” Rockport Sgt. James Moore wrote in his report of the call. “Krause stated to Haddad twice during the conversation, ‘I think I have to kill my mom.’ Haddad asked Krause to repeat himself, and that was when Krause stated it a second time,” according to court documents.

Groton police were called shortly before 6 p.m. on Sept. 8 and went to Elizabeth Krause’s parents’ house.

Orion Krause

Orion Krause, naked, covered in mud, with some blood on him, had stopped at a home in his grandparents’ neighborhood on Common Street to tell the resident he had killed four people. Krause repeated his statement that he had killed four people and identified who they were to police, according to the police report.

Krause is a 2013 graduate of Camden Hills Regional High School in Rockport and graduated in May from Oberlin Conservatory, where he studied music.

Friends say that Krause was a kind, musically gifted person. Krause had told a nurse during a medical evaluation that he uses heroin, according to the police reports.

Rockport police had one contact with Krause about a year before, but the details of that matter have not been released. Rockport/Camden Police Chief Randy Gagne said it was not a criminal matter.

Krause’s defense attorney, Edward Wayland, said in September that his client’s mental state at the time of his arrest was an open question.

“No one should make any assumptions about anything he is alleged to have said, including that any of it was actually true. Determining the truth is what the legal process is designed to do and it has barely begun to do it,” the attorney from Boston said in his statement last month.