Marc Barnes (left), Perley Goodrich Jr. (center) and Dominic Sylvester (right) Credit: BDN composite photo

Dominic Sylvester killed his grandmother in the Bowdoinham mobile home they shared in 2018, apparently after years of suffering severe abuse by multiple adults in his life.

Perley Goodrich Jr. had a 20-year history of mental illness when he pistol-whipped his mother, then used the same gun to kill his father in their Newport home in 2009 before fleeing into the woods.

And James Peaslee shot his step-father at his Bridgewater home in 2018 after a dispute over Peaslee’s mother’s estate.

The three killings are among the rare examples of children killing parents or step-parents in Maine over the past two decades, and they exemplify the three most common categories of parricide — the term used to describe a child killing a parent.

Of Maine’s 14 homicides so far this year, just one involves the slaying of a parent. Adam Groves, 44, has been charged with murder in the death of his mother Pauline Taylor, 63, at her home in Lincoln on Aug. 19. He is being held without bail at the Penobscot County Jail in Bangor.

The reasons why a child murders a parent, whether as a juvenile or adult, might seem inexplicable. But Kathleen Heide, a psychologist and professor of criminology at the University of Southern Florida in Tampa and author of the widely cited 2013 book “Understanding Parricide: When Sons and Daughters Kill Parents,” has theorized that children who murder a parent or step-parent are either the victims of abuse by the parent, suffer from a severe mental illness or are anti-social individuals who kill for selfish reasons.

Because so few details have been made public about Taylor’s death or what might have led up to the shooting, which category Groves might fall into, if any, is unclear. His attorney, Jeffrey Silverstein of Bangor, said after Groves’ first court appearance on Aug. 21 that his client acted out of fear during a “dangerous confrontation” at Taylor’s house, the lawyer said.

Silverstein has defended two other men charged with killing a parent, Marc Barnes and Perley Goodrich Jr. Both had histories of mental health issues and troubled relationships with their families.

“Familial dysfunction” probably factors into the circumstances that led to Taylor’s death, Silverstein said Friday.

While Groves’ case may not immediately fit into Heide’s categories, many of the parricide cases the Maine Attorney General’s office has prosecuted over the past two decades or so do fit. They also follow national statistics that show the defendant is much more likely to be male than female.

Heide and other researchers have found that abuse is the most common factor in cases like Dominic Sylvester’s, in which an adolescent kills a parent. Generally in such cases there is no history of mental illness, and the perpetrator acted spontaneously and often feels relief rather than remorse immediately after the slaying.

Sylvester, 19, is serving a 27-year sentence at the Maine State Prison in Warren for murdering the woman who raised and reportedly abused him. Sylvester was 16 when his maternal grandmother, guardian and adoptive mother, Beulah “Marie” Sylvester, 55, was found unconscious on Feb. 26, 2018, in their Bowdoinham mobile home. She later died.

After a judge determined Sylvester would be tried as an adult, he pleaded guilty to murder and admitted that “he had struck the victim in the head with a stick.” The victim suffered numerous cracked ribs, bruises, cuts, scrapes and a head injury, according to law enforcement officials.

A defense psychologist said that Sylvester suffered from severe abuse by multiple adults, including his grandmother, and had lived in “an incredibly chaotic, disruptive environment” from which he finally felt he had to save himself.

Heide’s research has shown that one of the major contributing factors in a child killing a parent is mental illness, most often untreated, as was Goodrich Jr.’s bipolar disorder. Although never formally diagnosed, Barnes had a history of mental instability but refused treatment.

Offenders may have hallucinations and hear voices, according to Heide. These voices can be perceived as instructions from God or another spiritual being telling them to kill a parent.

Goodrich Jr., now 56, of Newport had a 20-year history of mental illness when he pistol whipped his mother, Sandra Goodrich, now 75, then used the same gun to kill his father Perley Goodrich Sr., 76, on Oct. 26, 2009, and fled into the woods.

A jury found him not guilty of murder but guilty of manslaughter. Jurors also rejected his insanity defense. He was sentenced to 15 years in prison with all but eight suspended and four years of probation. Goodrich Jr. has served his sentence and completed probation, according to the Maine Department of Corrections.

Several witnesses, including his mother and mental health workers, testified during his six-day trial in 2011 that Goodrich Jr. virtually begged for help in the days leading up to his father’s killing. Specifically, he sought a prescription for the anti-anxiety drug Klonopin, which Goodrich maintained worked for him for several years until he was taken off it in 2008 after marijuana was found in his system.

On Oct. 25, 2009, Sandra Goodrich returned home to find her son with his bag packed and asking for a ride to the hospital. Goodrich Jr. was subsequently sent to the Dorothea Dix Psychiatric Center in Bangor but left and took a taxi home to Newport after he realized he would not be prescribed Klonopin.

Barnes, now 50, of Orono is serving a 65-year sentence at the state prison for murdering his mother, Barbara Barnes, 59, of Orono a few days before Christmas in 1999. Barnes fled Maine after killing her and was found five months later living in the New York City subway system.

Andrea Balcer (left) and James Peaslee (right) Credit: BDN composite photo

Anti-social offenders kill for primarily selfish reasons, according to Heide and other researchers. Parents might be stopping them from doing what they want, or the killers want access to money or property. They also may lack emotion or empathy. A famous example of this type are brothers Lyle and Erik Menendez. In 1989 they shot and killed their parents, Jose and Kitty Menendez, in their Beverly Hills, California, home to obtain full access to their wealth.

James Peaslee, 40, is serving a 60-year sentence at the state prison for shooting to death his step-father, Paul Hilenski Sr., 79, of Bridgewater in January 2018 in a dispute over Peaslee’s mother’s estate.

Prosecutors argued that the motive for the crime centered on Peaslee’s fury over a probate decision involving the estate of his mother, Janet Hilenski. After she died suddenly without a will, Hilenski Sr. was allowed to remain on the property after the case went through probate. Peaslee and his siblings received checks from the estate.

In sentencing Peaslee, Superior Court Justice Harold Stewart II said that Peaslee exhibited “no evidence of remorse,” had tried to blame his brother for the crime and had “committed almost an execution-style murder.” He also said that Peaslee had a significant criminal history, and there was a “suggestion he is anti-social.”

Another killer who may fit into this category is Andrea Balcer, 21, of Winthrop, who is serving a 40-year sentence at the state prison for stabbing to death her mother and father, Alice and Antonio Balcer, both 47, and the family dog on Oct. 31, 2016. Balcer, who was 17 at the time of the slayings, told staff at Long Creek Youth Development Center in South Portland that she was transgender and did not feel her parents would accept her as a female.

Balcer stabbed Alice repeatedly in the back while she was hugging the then-teenager. Andrea stabbed Antonio Balcer, who was awakened by his wife’s screams, in the kitchen. Finally, Balcer killed the dog because it would not stop barking. Alice Balcer was stabbed nine times and Antonio Balcer was stabbed a dozen times, according to the autopsy report.

When Superior Court Justice Daniel Billings ruled Balcer would be tried as an adult, the teenager made the decision to live in prison as a male using his birth name Andrew.

Researchers warn that while these categories are useful in explaining why children kill parents or step-parents, not all cases fit neatly into one or another. Offenders can exhibit behavior from one or more of them.