The Minnesota Security Hospital in St. Peter marked a major turning point this week, as state regulators lifted long-standing licensing restrictions that were imposed over persistent breakdowns in patient care and safety.

The state's largest psychiatric hospital, which treats about 360 of Minnesota's most dangerous and psychiatrically complex patients, has been operating under a conditional license for the past five years as it struggled to protect patients and staff from violence.

State officials cited progress in the hospital's multiyear effort to create a more therapeutic environment and to root out the punitive culture that once dominated the facility.

In a memo to staff Thursday, state Human Services Commissioner Emily Piper said the facility has made "significant progress on many fronts" and will now be fully licensed by the state.

"This is a recognition that we have really turned the corner at the Security Hospital," Piper said in an interview.

The security hospital has been under intense regulatory scrutiny since 2011, when state investigators found the facility was placing too many patients in restraints and seclusion, even in nonemergency situations, and for much too long. The conditional license was extended another two years in early 2014, after a 41-year-old patient was stomped to death in his room — a murder that state investigators later blamed on poor supervision.

Under new leadership, the hospital launched a series of reforms designed to improve engagement between hospital staff and patients. The hospital trained hundreds of staff on how to identify potentially violent situations, and to redirect and calm agitated patients rather than resorting to physical restraints and seclusion. The hospital has also implemented more individualized treatment plans, with better communication between treatment teams.

And for the first time, the Security Hospital has given family members of patients a more direct say in the facility's day-to-day operations. A family advisory council, composed primarily of mothers of patients, has made a number of recommendations on how to make the hospital more therapeutic and less prisonlike.

The reforms appear to have taken hold. The number of injuries from patient aggression, which have long plagued the hospital, fell by nearly half this year, to 57 injuries from 100 in 2015. Overall, workplace injuries at the hospital are down by nearly 40 percent over the past year, state records show.

"Do I still think the hospital should be providing more treatment? Absolutely," said Sue Abderholden, executive director of the National Alliance on Mental Illness of Minnesota. "But there's no question things have really turned around. There seems to be much greater cohesion among staff."

Even so, Piper made it clear that her agency would push for further improvements. Last year, the Department of Human Services sought $70.3 million to make safety improvements at the hospital, but the request died in the 2016 Legislature. Piper said the agency will seek those funds again, as well as millions more to bring the hospital's staffing up to comparable ratios at mental facilities in other states.

"I'm really proud of the work that we've done," Piper said, "but the Legislature has an obligation to fully fund [the Security Hospital]. And so far, it's not fulfilling that obligation."

Chris Serres • 612-673-4308

Twitter: @chrisserres