Orion Krause right, stands with his attorney Edward Wayland at Krause's arraignment in Ayer District Court in Ayer, Mass., Monday, Sept. 11, 2017. Krause, of Rockport, Maine, was ordered held without bail at Bridgewater State Hospital pending a competency hearing at his arraignment on murder charges Monday in Ayer. Credit: Josh Reynolds | AP

Nearly three months after his trial was slated to start, the Rockport man accused of a quadruple homicide in Massachusetts is still waiting to undergo a psychiatric evaluation that will determine the course of his case.

The trial for Orion Krause was scheduled to begin in April. But in March his attorney entered an insanity plea on behalf of Krause, delaying the trial until prosecutors could find an expert to conduct their own evaluation.

Krause is charged with four counts of murder for the Sept. 8, 2017, beating deaths of his mother, Elizabeth “Buffy” Krause, 60; her parents, Elizabeth “Esu” Lackey, 85, and Frank Danby “Dan” Lackey III, 89; and their home health aide, Bertha Mae Parker, 68, at the Lackeys’ house in Groton, Massachusetts.

If convicted on all four charges, Krause faces a maximum of four life sentences without the possibility of parole.

In October 2017, Krause was found competent to stand trial. But when Krause entered not guilty pleas on all counts last year, his attorney, Edward Wayland, told the BDN that “mental illness is the entire explanation for this tragedy.”

A mental health expert who examined Krause prior to trial on behalf of the defense found that the cause of the homicides was mental illness. Meaning that, “Orion was compelled by his mental illness to act as he did and is therefore not criminally responsible,” Wayland told the BDN in an email Tuesday.

Now, the Middlesex District Attorney’s Office will need to find its own expert to evaluate the case, including Krause himself, and make an independent determination about whether mental illness caused the crime.

If the state’s expert finds that mental illness is in fact to blame for the murders, Wayland said “Orion would be found not guilty by reason of insanity and committed to a mental institution.”

However, if the state’s expert finds that mental illness was not the cause, the case will go to trial and both the defense’s expert and the state’s expert will testify, Wayland said.

Despite entering the insanity plea March 7, Wayland said he is still waiting to hear from the district attorney’s office that they have found an expert to conduct an evaluation.

Messages left with the Middlesex District Attorney’s Office on Monday regarding why it has taken nearly four months to find an expert have not been returned.

Krause allegedly admitted to investigators that he killed four people with a baseball bat at his grandparents’ home, according to police reports from the Sept. 8, 2017 incident.

Police found the bodies of Krause’s mother and grandparents sitting in chairs in the kitchen. Parker’s body was found in a flower bed, according to the report.

Krause allegedly told investigators that he “freed them.”

On the night of the killings, Krause allegedly called a former college professor and said, “I think I have to kill my mom.”