From a distance, the campus of Napa State hospital, in Northern California's wine country, looks like a small suburban office park. Buildings are fringed by a wide lawn.
But on the perimeter is a tall metal fence, topped by barbed wire. Napa State, which is managed by California's Department of State Hospitals, is no ordinary psychiatric hospital.
Since the mid-1990s, more than 80 percent of Napa's patients have been referred here by the criminal justice system. Some of them committed horrific crimes but were found not guilty by reason of insanity, or incompetent to stand trial. Instead of being set free or sent to prison, they were ordered to a psychiatric hospital.
Here, anyone who enters the secure area — workers and visitors alike — all pass through multiple doors, metal detectors and locked gates.
The vast majority of people with mental illness aren't violent. But statistics on assaults suggest that some patients at Napa State Hospital are dangerous — to patients as well as to staff. Last year alone, the hospital says, patients committed more than 1,800 physical assaults.
For staff at Napa State, this week marks a somber anniversary. It was here, on October 23, 2010, that psychiatric technician Donna Gross was murdered by a patient — grabbed, dragged and strangled to death.
"Everyone who was here the day that Donna died on these grounds has PTSD, and we will never be able to address it," says Michael Jarschke, who has worked as a psychiatric technician at Napa State Hospital for 32 years. "We just carry it," he says. "It's there."
At the time of Gross' murder, staff members all carried alarms to call for help. But back then, Jarschke says, the alarm only worked inside the buildings — not outside, where Gross was murdered.
"When you think about it today, that's almost ludicrous that we would do this," Jarschke says. "We always look back five years [later] and say, 'Wow, we were really dumb back then.' "
Soon after the murder, as president of the union representing psychiatric technicians, Jarschke helped form Safety Now Coalition, a group of employees who got together to demand change.
Dolly Matteucci, the hospital's executive director, says the hospital has made changes in the last five years — like limiting the ability of potentially dangerous patients to walk around freely.
"At this point in time, we have a much more stringent and informed and comprehensive grounds-access policy," Matteucci says.
Matteucci describes the most important change at Napa — a new personal alarm system with GPS to help hospital police respond more quickly to emergencies anywhere on the grounds. She has one hanging around her neck and explains that pulling it sends an immediate notification to all hospital police and their dispatch center.
Staff members sound that alarm frequently.
The tags gets pulled 11 to 17 times a day, Matteucci says. "Staff might see a patient escalating and say, 'That's looking a little precarious. I want a little help before I engage that patient.' "
She says that the heavy use of the alarm system illustrates how difficult it can be to serve such a challenging population "in a very complex, active environment that was not built for a forensic patient population."
Napa State Hospital opened in 1875. Until about 20 years ago, most of its patients were civil commitments. Courts ordered people to the psychiatric hospital because acute or chronic symptoms of serious mental illness suggested they were a risk to themselves or others. But there was no criminal wrongdoing involved.
Today, a substantial majority of patients at Napa State Hospital come through the criminal courts. Some have been been involved in criminal gangs.
To address that shift in the population, Matteucci says, Napa has added more hospital police. But workers say the hospital remains a dangerous place for staff.
At a June 2014 hearing of the health committee in California's State Senate last year, psychiatric technician Stephanie Diaz gave tearful, halting testimony, recounting her recent experience with one patient. As she was escorting him up a stairwell, she said, he tripped her, pinned her to the floor and attempted to rape her.
"I started screaming at the top of my lungs," she told the committee, "praying that someone would hear me." She wasn't sure if she'd properly pulled the alarm, she said. "After a slight delay, I heard the alarm sound and help arrived. It felt like an eternity. And I feared for my life."
Diaz was testifying on behalf of legislation that would allow California's five state mental hospitals to isolate the most dangerous patients, and give them more intensive treatment. The bill, AB 1340, passed both houses of the state legislature and was signed into law by Gov. Jerry Brown on Sept. 28, 2014. But it will take at least another year to remodel the facilities and fully implement the law, officials say.
Napa psychiatrist Steve Seager is a vocal critic of the hospital administration. He says much more needs to be done to protect both patients and staff.
"Violence is part of our life every day," he says. "It's just a constant thing. It's not like violence happens now and again. Violence is part of the daily life at Napa."
And that prompts a question: Why would anyone want to work here?
Seager quotes the simple answer of one of the staff nurses at Napa State has a simple answer: "This is a Jesus job."
"The patients need treatment," Seager says. "They're criminals. ... They've committed crimes. I never forget that. But they deserve to be treated with dignity, which we try and do."
This post was produced by KQED's State of Health blog.