"We are starting the process of closing death row to repurpose and transform the current housing units into something innovative and anchored in rehabilitation," California Department of Corrections and Rehabilitation spokeswoman Vicky Waters told The Associated Press.
Oregon similarly transferred its much smaller condemned population to other inmate housing two years ago.
Newsom, a Democrat, imposed a moratorium on executions in 2019 and shut down the state's execution chamber at San Quentin, north of San Francisco. Now his administration is turning on its head a 2016 voter-approved initiative intended to expedite executions by capitalising on one provision that allowed inmates to be moved off death row.
"The underlying motive of the administration is to mainstream as many of these condemned murderers as possible," said Michael Rushford, president of the Criminal Justice Legal Foundation, which backed the initiative. "Our objective was to speed up the process."
He added he doesn't think victims are happy with the administration's decision.
"They're moving condemned murderers into facilities that are going to make their lives better and offer them more amenities, while the victims still mourn the death of their family member," Rushford said.
Newsom said voters approved the move, though he doubts many understood the provision.
"When they affirmed the death penalty, they also affirmed a responsibility ... to actually move that population on death row out and to get them working," Newsom said.
Newsom is "pouring more salt on the wounds of the victims," countered Crime Victims United of California president Nina Salarno. "He's usurping the law."
Actor Mike Farrell, president of the group Death Penalty Focus, which opposes the death penalty, said he is thrilled with the idea but concerned by transfers he said could turn condemned inmates into "very ripe targets" for other prisoners.
"We're talking about people who have been in a specific kind of isolation for decades," living with the prospect of execution, Farrell said. "To simply move them without very serious consideration of their needs, their personal issues, their psychological state and their safety would be a hideous mistake."
Corrections officials began a voluntary two-year pilot programme in January 2020 that as of Friday had moved 116 of the state's 673 condemned male inmates to one of seven other prisons that have maximum security facilities and are surrounded by lethal electrified fences.
They intend to submit permanent proposed regulations within weeks that would make the transfers mandatory and "allow for the repurposing of all death row housing units", Waters said.
The ballot measure approved six years ago also required condemned inmates to participate in prison jobs, with 70 per cent of the money going for restitution to their victims, and corrections officials said that's their goal with the transfers. By the end of last year, more than $49,000 in restitution had been collected under the pilot programme.
Newsom's proposed budget for the fiscal year starting July 1 seeks $1.5 million (NZD$2.2m) to find new uses for the vacant condemned housing.
It notes that death row and its supporting activities are in the same area as facilities used for rehabilitation programmes for medium-security San Quentin inmates. The money would be used to hire a consultant to "develop options for (the) space focused on creating a positive, healing environment to provide increased rehabilitative, educational and health care opportunities."
San Quentin's never-used $853,000 (NZ$1.2m) execution chamber is in a separate area of the prison, and there are no plans to "repurpose" that area, Waters said.
California voters supported the death penalty in 2012 and 2016. An advisory panel to Newsom and lawmakers, the Committee on Revision of the Penal Code, in November became the latest to recommend repealing the death penalty, calling it "beyond repair."
Under the state's transfer programme, condemned inmates moved to other prisons can be housed in solitary or disciplinary confinement if officials decide they cannot be safely housed with others, although they are supposed to be interspersed with other inmates.
Inmates on death row are housed one to a cell, but the transferred inmates can be housed with others if it's deemed safe.
"There have been no safety concerns, and no major disciplinary issues have occurred," Waters said.
When it comes to jobs and other rehabilitation activities, condemned inmates outside death row are treated similarly to inmates serving sentences of life without parole. That includes a variety of jobs such as maintenance and administrative duties, according to prison officials.
The condemned inmates are counted more often and are constantly supervised during activities, officials said.
Before they are moved, they are "carefully screened to determine whether they can safely participate in the programme", according to the department. That includes things like each inmate's security level, medical, psychiatric and other needs, their behaviour, safety concerns and notoriety.
Female condemned inmates are housed at the Central California Women's Facility in Chowchilla. They can transfer to less restrictive housing within the same prison, and eight of the 21 have done so.