Lawmakers nixed reforms to solitary confinement in Minnesota prisons this week, eliciting criticisms from mental health groups and the bill's author, who say more safeguards are key to keeping the state accountable for its treatment of vulnerable inmates.

Rep. Nick Zerwas, R-Elk River, who carried the bill, blamed Gov. Mark Dayton and the Department of Corrections for the late collapse of a last-ditch deal.

"At the end of the day, it wasn't the highest priority to the Dayton administration and the Department of Corrections," Zerwas said. "Offers were traded back and forth and they chose other funding areas to focus on."

Zerwas's original bill would have limited the length of solitary confinement usage, banned the practice for mentally ill inmates and no longer allowed the state to release people from prison directly from solitary. It also mandated that prison officials report annual data to lawmakers on who is going to segregation and for how long.

Dayton also wanted reform, and requested $7 million to expand resources for solitary and mental health care in state prisons. He challenged Zerwas' claims that he was responsible for the measure's demise.

"I strongly support restrictive housing reform, which is why I put it in my budget. Any assertion that says otherwise is categorically false," Dayton said in a statement. "Republicans prioritized massive tax giveaways for the wealthy, tobacco companies, and big businesses ahead of supporting these essential reforms and investments in public safety."

Earlier this month, Senate leadership removed the solitary language from a larger package of public safety bills. Zerwas said Republicans threw back in the funding earlier this week, along with the bump for mental health expansion, but Dayton's administration wanted to spend it on DOC elsewhere.

Sue Abderholden, executive director of Minnesota's National Alliance on Mental Illness chapter, said she was disappointed policymakers couldn't come to an agreement, particularly after Zerwas amended the bill to eliminate costs and refocus on getting more transparency from prison officials.

"It wasn't banning it," she said. "It was just helping us get better information and making sure there was oversight ... This was not an unreasonable bill by any stretch of the imagination."

The push for reform came after a December 2016 Star Tribune report examining solitary practices in Minnesota. In a 10-year period, more than 1,600 inmates spent six months or more in isolation and 413 served one year or longer. Prisons regularly send mentally ill inmates to solitary, and some deteriorated in isolation and continued to misbehave, which led to even more segregation time. One inmate served more than 10 years, even with a diagnosis of a severe mental illness.

Dayton reported in his original budget proposal that Minnesota prisons have seen a 20 percent increase in offenders with serious and persistent mental illnesses over the past seven years, with 11 percent of prisoners living in solitary confinement having such a diagnosis.