A lengthy and vocal campaign to strictly limit solitary confinement in New Jersey’s prisons came to a close Thursday when Gov. Phil Murphy signed a long-stalled reform measure into law.

“I am proud to stand together with New Jersey’s criminal justice reform advocates and legislators to advance a humane correctional system that allows for the safe operation of facilities and focuses on strengthening reentry initiatives, substance use disorder treatment, and recovery programs,” the Democratic governor said in a signing statement Thursday.

Supporters say the measure is among the most comprehensive controls on the controversial practice of placing prisoners in isolation in the United States.

Its passage followed several years of debate in the state Legislature that culminated in 2016 when then-Gov. Chris Christie trashed the proposal, claiming solitary confinement did not happen behind bars in the Garden State.

It was a position long held by corrections officials in New Jersey, where prisoners could be placed in “restrictive housing,” “protective custody,” “administrative segregation” and other methods of isolation.

There are many reasons why corrections officials might need to remove an inmate from the general population, including for their own safety or because they pose a danger to other prisoners.

The current acting corrections commissioner, Marcus Hicks, said in a statement Thursday that the new law “will codify certain existing New Jersey Department of Corrections policies into law and prevent isolated confinement from wrongful overuse in the state of New Jersey by future administrations,” suggesting the practice was not currently an issue in the state’s prison system.

But prison reform and civil rights advocates have long argued the bureaucratic language used by the corrections department obscures how often inmates are placed in isolation as an act of punishment or retaliation.

In recent months, a coalition of advocacy groups under the banner of the NJ Campaign for Alternatives to Isolated Confinement renewed a push to strictly curtail the practice, collecting testimony of inmates who claimed they spent months in isolation.

“The agony of solitary confinement is that it doesn’t just lock up your body – it locks in your mind," said Nafeesah Goldsmith, a community organizer who says she spent 60 days in solitary confinement while serving a New Jersey prison sentence.

“For New Jersey to institute dramatic restrictions on solitary acknowledges the suffering we’ve endured, along with the scars we’ll bear for the rest of our lives.”

The push by advocates is part of a national movement of prison reformers who say solitary confinement is inhumane.

“Solitary confinement is torture," U.S. Sen. Cory Booker said in a statement applauding the new law. “It is an archaic, damaging, and inefficient practice that has been proven to have irreversible effects. Yet, thousands of Americans are held in isolation daily.”

The measure (A314) passed the state Legislature again earlier this year with dozens of sponsors.

The new law prohibits the use of solitary “unless there is reasonable cause to believe that the inmate or others would be at substantial risk of serious harm as evidenced by recent threats or conduct."

It places even more restriction on the practice for members of “vulnerable populations,” including prisoners under 21 or over 65, LGBTQ inmates and those who are pregnant or disabled. It also requires that no inmate be isolated for more than 20 days in a row, or for more than 30 days during any 60-day period.

The law, which applies to the state’s jails, prisons, and other detention facilities, requires mental health evaluations for prisoners placed in temporary isolation as well as better data collection and reporting

It goes into effect in August of next year.

S.P. Sullivan may be reached at ssullivan@njadvancemedia.com. Follow him on Twitter. Find NJ.com on Facebook.

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