Updated 1:24 p.m.

A violent episode between a California Highway Patrol officer and his wife on Monday marks the second murder-suicide in Amador County in a span of five months.

The 45-year-old off-duty patrol officer shot his 42-year-old wife at a store in Martell, which is an hour east of Sacramento before turning the gun on himself, according to The Associated Press. Another man who was in the store called the authorities, and was shot in the shoulder during a struggle involving all three parties. He is being treated in a hospital.

This comes about five months after a 26-year-old man killed his girlfriend, his father and himself in Pine Grove, which is 15 minutes from Martell.

These killings often rattle close-knit communities in the country. And while murder-suicide shares some risk factors with suicide, the latter happens at much higher rates in California’s rural counties. This is often due to a lack of mental health services and many other factors that you can read about on our Amador project page.

But unlike an individual who decides to end their own life, murder-suicide cases are almost always tied to domestic abuse and broken families.

“Suicide is an equal-opportunity employer,” said Donna Cohen, a professor in the University of South Florida’s Department of Child and Family Studies. “Murder-suicide is sort of a different animal.”

She means that while both suicide and murder-suicide can be traced back to depression, murder-suicide has more to do with conflict between lovers or family members. Perpetrators are usually men who’ve had control their entire lives, and they’re motivated by a specific goal, such as getting back at a romantic partner, Cohen said.

On a Thursday morning in April, 26-year-old Jacob Jedidiah Thayer killed his girlfriend, 27-year-old Marie Ann Leonetti, and his father, 60-year-old Richard Roger Thayer I, before shooting himself in their home, according to reports in the Amador Ledger.

For a while, everyone in town was talking about the killings. Thayer’s former classmates, co-workers and teachers wondered how the situation took such a gruesome turn.

Tammie Crabtree, director of an Amador County domestic violence nonprofit called Operation Care, said after years of abuse, even a small conflict can send an aggressive partner over the edge.

“It seems to be a threat, often ‘I love you, if you don’t come back to me I’m going to kill you and then myself’,” she said. “It’s a very common threat, we hear it pretty often.”

She said she’s learned to look “at every situation with a definite potential for violence.” When her staff work with women who are too afraid to leave these threatening partners, they take concrete measures like file restraining orders and finding safehouses.

But there’s another type of murder-suicide with a very different profile: cases that happen among seniors.

Cohen said it’s common to have older men caring for their wives for many years. “Older men who are caregivers, they have to do something, they’re task-oriented and they’re goal-driven,” she said. “When they can’t do anything else, in their depression they’re just coming up against a brick wall and see no other recourse than to kill the person.”

Regardless of the motivation, murder-suicides are most often committed using a firearm. There isn’t a comprehensive national database for these deaths, but the Washington, D.C.-based Violence Policy Center did its own tracking and found that nine of 10 murder-suicides involve a gun, and in nearly two-thirds of all cases an intimate partner of the shooter is among the victims. They don’t know whether these crimes are more likely to happen in rural or urban areas.

But Cohen said this level of violence causes a huge ripple through communities regardless of the location. And because they involve parents, children, in-laws and other relatives, “the ramifications go through generations, down to the grandchildren. They can really “shake the fabric of the family system,” she said.

She called the crime a “tip of the iceberg” for deeper problems in families and communities.

“What we find is this kind of mass death just doesn’t go away,” she said. “These are preventable, but we don’t know how to prevent them yet.”

Correction: A previous version of this story misstated the time of day that the April crime occurred. It was a Thursday morning.

If you or someone you know needs help, call the National Suicide Prevention Lifeline at 1-800-273-8255. Additional resources for those in Amador County and beyond, including programs for youth, seniors, veterans and Native Americans, can be found here.

This project is funded by a USC Annenberg Center for Health Journalism grant.