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Brockton Man Found Not Guilty By Reason Of Insanity In Mother’s Murder

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Contact: Beth Stone 508-584-8120

BROCKTON – A Brockton man was found not guilty by reason of insanity in the 2016 murder of his mother, Plymouth County District Attorney Timothy J. Cruz has announced.

After a two-day bench trial concluded late yesterday, Brockton Superior Court Judge Angel Kelley found Frantz Polynice, now 23, not guilty by reason of insanity in the stabbing death of his mother. Polynice was charged with one count of Murder and two counts of Assault and Battery with a Deadly Weapon. Polynice was committed to Bridgewater State Hospital where Polynice had been previously receiving treatment while awaiting trial.

 At approximately 12:30 pm on November 30, 2016, Brockton Police received a 911 call from a neighbor. The neighbor, who resided at 34 Merritt Avenue, called on behalf of a woman who had appeared at her door hysterical and spoke Haitian Creole. The woman motioned for the neighbor to follow her back to 34 Merritt Avenue where they entered a side door to the kitchen. As they entered the kitchen, Polynice exited the home’s living room and approached the women wielding a knife. The women ran from the house and stood in the street. Polynice exited the home and sat on the porch steps until emergency personnel arrived.

Brockton Police and emergency medical personnel located 44-year-old Mania Menieda lying on the living room floor with multiple stab wounds. She was transported to Signature Hospital in Brockton where she was pronounced dead at 1:36 pm. Menieda was the mother of Polynice.

Investigators interviewed family members who reported that Polynice had refused to eat or drink in the days before the murder. Investigators also learned that Meneida had attempted to get Polynice help and return him to live with an aunt in Haiti but he refused. An autopsy revealed that Polynice stabbed Meneida numerous times about the head and face and upper torso.

At trial, three experts who examined Polynice, and records from before, during, and after the murder, all opined that Polynice was “lacking in criminal responsibility” at the time of the event.   

Assistant District Attorneys Richard Linehan and Tricia Reilly prosecuted the case, which was investigated by State Police Detectives assigned to the Plymouth County District Attorney’s Office and Brockton Police.

March 26, 2021