What's behind the growing trend of a person, most often a man, killing their own family?

IndyStar examined 227 "family annihilation" cases that occurred from Jan. 1, 2020 to April 30, 2023, and found several common threads in the tragedies that killed more than 750.

Three scenarios repeatedly jumped out from the data: Men who killed their wives or girlfriends and children; young men who killed their parents and siblings; and couples who conspired to kill their children and themselves.

In the majority of cases analyzed by IndyStar, neither the police, surviving family nor media reports revealed a reason for the killings or other key stressors. As a result, contributing factors are likely undercounted.

Still, the cases reveal a number of telling trends and patterns:

September 6, 2020 - Bloomington, Indiana, USA: The Bloomington Police Department investigates after a triple murder-suicide that left four community members dead at a home in the 2600 block of S. Olcott Blvd., in the Hyde Park neighborhood. The motive for shootings is unknown, and police continue to investigate.  (Photo by Jeremy Hogan/The Bloomingtonian)

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Prior domestic violence

In at least 38 cases, prior domestic violence was documented by police records, court orders or the victims' family. In Florida, a man beat his ex-girlfriend and took their 7-month-old baby. Two weeks later, the violence escalated: he shot and killed the woman, their child and himself.

Prior criminal history

At least 34 family annihilators had prior criminal records. Their crimes range from misdemeanor drug and theft offenses to felonies like aggravated assault, animal cruelty, rape and manslaughter. A Tennessee man at the center of a child abuse investigation killed his wife, 17-year-old daughter and himself the week after a grand jury indicted him.

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Mental illness and stress disorder

In at least 33 cases, perpetrators reportedly had mental illnesses, including depression, bipolar disorder, post-traumatic stress disorder and schizophrenia. An Arizona man shot his wife and 11-month-old daughter. He told investigators he made a deal with a spirit to kill his wife so they could be together forever.

GET HELP: Resources for suicidal thoughts, child abuse, mental health, domestic violence

Jealousy and control

In at least 14 cases, perpetrators reportedly killed out of jealousy or to control their victims — most commonly when a female partner tried to leave the relationship. A South Carolina man shot his ex and her daughters after she went to the beach with another man.

Money and job problems

In at least eight cases, perpetrators were facing money problems, job loss or even eviction. An Oklahoma couple with $138,000 in student loans debt killed their six children and themselves.

Drugs and alcohol

Only 4 perpetrators reportedly had drugs or alcohol in their systems when they killed their families. A Colorado man said he blacked out from drinking tequila when he shot his mother and teenage siblings.

Serious illness or debilitating conditions

In at least 13 cases, perpetrators or victims had documented illnesses or disabilities. Some family annihilators had significant diagnoses, including cancer, Parkinson’s disease and traumatic brain injuries. Others were caretakers under pressure.

“We are in an impossible situation with no way out,” a Florida man told a 911 dispatcher after he killed his wife and stepdaughter — both of whom had terminal illnesses. “I have to go, I’m fixing to shoot myself.”

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This article originally appeared on Indianapolis Star: IndyStar investigates family annihilation: What's behind the trend?