Perhaps the largest group of mentally ill inmates in the U.S. resides in Los Angeles in one of the world's largest jail complexes.
Over the past seven years, the jail's population has spiked almost 50 percent — with nearly every inmate having both mental illness and substance abuse problems — and officials suspect the rise is due to methamphetamine.
The Twin Towers Correctional Facility is home to about 4,000 mentally ill inmates. The increase in the number of mentally ill prisoners — about 30 percent of the county's total jail population — has led the sheriff's department to adapt its policies as deputies and clinicians work to treat people dealing with both psychiatric disorders and substance abuse.
Los Angeles County Sheriff Jim McDonnell has blamed the surge on meth use, but doctors say it's often difficult to distinguish whether the patients had underlying conditions and then started using drugs, or if their chronic drug use led to psychiatric disorders.
Chronic use of meth, a highly addictive stimulant, can cause paranoia, visual and auditory hallucinations and delusions, studies have shown.
"It's causing people previously healthy to become mentally ill, and we're going to be dealing with those individuals in one way or another for the rest of their lives," McDonnell said.
Sheriff's officials say they've started training deputies specifically in dealing with mental illness and focusing on treatment instead of punishment.
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"No one ever expected jails and prisons to be mental health institutions," said Kelly Harrington, the assistant sheriff in Los Angeles who oversees the county jail system. "The deputies, although they don't have specific psychiatric- or psychology-type degrees, we give them as much training as we possibly can in the short period of time we have them."
The American Civil Liberties Union routinely receives complaints from Twin Towers inmates who say they haven't been able to see doctors or psychiatrists, haven't received their medication and that their medical needs are being ignored, said Esther Lim, Jails Project director at the ACLU of Southern California.
"The jail has a history of not providing adequate medical care or mental health care," she said.
Harrington said he has heard similar complaints but noted the jail system has made significant progress in recent years to ensure inmates receive proper care. Still, he concedes, more work needs to be done.
Over the past year, the sheriff's department has rolled out new training programs that focus on de-escalating potentially violent situations and teach deputies to handle mentally ill inmates, Harrington said. They also have adopted new techniques and programs that bring the inmates out of their cells for recreational programs and therapy.
In addition, county officials have launched a program to transition mentally ill inmates with substance abuse problems to continue their treatment in community programs so they don't return to a life of crime to get quick cash to buy drugs.
On a recent afternoon at Twin Towers, inmates took part in life skills lessons, substance abuse counseling, and classes to earn a GED diploma. Some inmates met one-on-one with clinicians to discuss their progress, while others chatted with peer mentors and passed the time playing cards and checkers.
Twin Towers inmates spend nearly all of their days in contained jail blocks. Some are segregated into pods because of their crimes, sexual orientation or gender. Cages give those who are housed in high-observation units and checked every 15 minutes some time outside their cells.
On the jail's fourth floor, inmates clad in their yellow scrubs sat at small tables around their cells and had a group discussion about the harms of substance abuse. They seemed to cling to every word from teacher Edward Monteilh.
"I really want them to understand how their brain works," said Monteilh, who has led classes at the jail for about five years. "I try to explain to them how mental illness affects them, how substances affect their brains and the compound effects of the two."
Even as sheriff's officials work to implement new programs and treatment initiatives, experts say the restrictive settings often can lead mentally ill prisoners who are already more likely to break jail rules to become more symptomatic and violent.
"That kind of isolation is not going to help your psychosis in any way, shape or form," said Dr. Jeffrey Reynolds, a social worker who specializes in substance abuse and addiction disorders. "They are probably walking out in a lot worse shape than they were than they went in."
And access to drugs inside the jails only makes the problem more complex. Between 2011 and 2016, the amount of meth recovered during searches inside Los Angeles county jails increased by nearly 750 percent.
Jail officials across the nation are struggling with how to deal with mentally ill inmates, including those who are also addicted to drugs.
A 2014 report by the Treatment Advocacy Center and the National Sheriffs' Association found 10 times more mentally ill inmates in America's jails and prisons than in its state hospitals. The report also showed the number of mentally ill prisoners and the severity of their conditions continued to climb.
"That cycle is feeding off itself, and we end up with what was initially a health problem as a very expensive criminal justice problem for years to come," McDonnell said.