Police Investigating Motive in Son's Killing of Mother

Rohnert Park police are awaiting autopsy and toxicology results from the body of Dennis Hughes, 41, who was shot and killed by police this week after he bludgeoned his mother to death with a baseball bat in her quiet B Section home.

The body of Dianne Hughes, surrounded in a pool of her own blood, was discovered hunched over on her living room floor by police Tuesday afternoon, after family members made repeated calls to authorities asking they check on her. Her white SUV was missing and they were worried.

Police confirmed to Rohnert Park Patch yesterday that the murder weapon was a baseball bat.

Dianne Hughes, 66, longtime Rohnert Park resident, was killed by her son, police discovered Wednesday night. Evidence led authorities to the edge of San Francisco's Tenderloin neighborhood, where Dennis barricaded himself in his girlfriend's apartment.

Three detectives from the Department of Public Safety, along with more than a hundred other public safety officers, from the San Francisco Police Department, the fire department and SWAT, converged on Hyde and Post streets shortly before 10 p.m.

When police arrive, Hughes had become erratic, firing shots at random from two handguns, prompting police to declare him a "significant threat to public safety."

That's why police said they had to "neutralize" him, as San Francisco's police chief described it.

A sharpshooter shot Hughes in the head from the third floor of an adjacent apartment building.

Now, police are piecing together the bizzare chain of events, and investigating the motive of Dennis Hughes, who one Patch reader described as nice.

"Dennis was a wonderful, loving, nice person," the reader wrote. "Something in him snapped and he did a horrible sad thing. I will always remmember the sweet fun person that he was when I spent time with him. My prayers go out to his daughter and family."

Rohnert Park police said late Friday that as soon as San Francisco police get autopsy results and related toxicology tests back, they'll be able to proceed.

"It's obvious he's dead because of a shot to the head," said Lt. Jeff Taylor, a spokesman for the Department of Public Safety. "But we're waiting for the toxicology to come back to see if he was on drugs."

Police speculated to the son's motive. They told various media outlets, from Patch, to the San Francisco Chronicle, the Examiner and the Press Democrat, that the son may have been angered because his mom asked him to move out of the house on Bernice Avenue.

One account reported that he'd ruined something sentimental to his mom. The Press Democrat reported today that:

"And then he destroyed sentimental property — a teddy bear from a deceased friend of mom," said Taylor. After that, she again told him he had to leave.

But Taylor insisted late Friday that they're still figuring it out, working with family members, neighbors and the girlfriend of Dennis — anyone who knows anything at all.

"We are trying to figure out why he did this." Taylor said. "Detectives are in the stages right now of writing reports, processing her car, gathering information. As soon as we get toxicology results from Dennis, it’ll help us with our motive for the murder of Dianne."

The SFPD is conducting the autopsy and medical tests.

"We have no control over that," Taylor said.

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