Gov. Arnold Schwarzenegger said Monday that the state could save $1 billion by building and operating prisons in Mexico to house undocumented felons who are currently imprisoned in California.

The governor floated the idea during an appearance at the Sacramento Press Club in response to a question about controlling state spending. His speech came on the same day that changes in prisoner parole and credits for time served took effect.

"We pay them to build the prisons down in Mexico and then we have those undocumented immigrants be down there in a prison. ... And all this, it would be half the cost to build the prisons and half the cost to run the prisons," Schwarzenegger said, predicting it would save the state $1 billion that could be spent on higher education.

About 19,000 of the state's 171,000 prisoners are illegal immigrants, according to the most recent statistics available online. The state spends more than $8 billion a year on the prison system.

Aaron McLear, spokesman for the governor, said later that Schwarzenegger's comments did not represent a concrete proposal, but "a concept somebody mentioned to him" and he could not say where the governor came up with the $1 billion figure.

The governor's statements seemed to catch his prisons chief off guard. Matthew Cate, secretary of the Department of Corrections and Rehabilitation, said it was not a proposal the department was pursuing and he assumed it was an extension of Schwarzenegger's call to privatize some of the state's prison operations.

Privatizing prisons

In his State of the State speech earlier this month, Schwarzenegger called for allowing private companies to compete with state-run prisons, which, he said, could save billions of dollars.

After the governor spoke Monday, Cate said the department has not reviewed or analyzed the Mexico proposal and said the department has no projections of how much money the state could save. He also acknowledged it could raise a host of jurisdictional and other issues.

"It would probably be complicated, but without looking into it yet, I'm not sure," said Cate, who was present at the Press Club event.

California is currently under a federal court order to reduce its prison population by 40,000 inmates over the next two years. A federal judge installed a receiver in 2006 to oversee inmate health care in state prisons, finding that substandard care led to the death of about one prisoner per week.

Donald Specter, director of the Prison Law Office, which sued the state on behalf of prisoners, said the governor's idea was "not very practical."

"It would be like the state of California having a separate island of its own government in Mexico. It just seems like that would be impossible," Specter said.

The governor's idea also drew criticism from the prison guards union.

"There are a number of reasons why it not only won't work, but shouldn't work," said Lance Corcoran, spokesman for the California Correctional Peace Officers Association. "There is no obligation from a sovereign nation to incarcerate and rehabilitate individuals who have not committed crimes within their borders."

Nearly any change in how California manages its prisons spurs controversy.

On Monday, some lawmakers were criticizing laws on parole and sentencing reductions that took effect this week. The changes, which were part of last year's budget negotiations, will reduce the state's prison population by about 6,500 inmates this year, according to the corrections department.

Changes criticized

That will mean people who are regarded as low-risk parolees will not be monitored by a parole agent and prisoners can earn additional credits for time served in prison, which would reduce their sentences.

Those changes were criticized by both Republicans and Democrats, including Assemblyman Ted Lieu, D-Torrance (Los Angeles County), who is a candidate for state attorney general. Lieu co-authored legislation introduced Monday to require local authorities to be involved in those parole decisions and for the state to notify local officials when people are given early release into their jurisdictions. He said the changes threaten public safety.

"I guarantee you crime will increase and there will be more victims of crime," he said.

Cate disputed that assessment, predicting the number of people who commit crimes again and return to prison would fall, as they would earn credits for completing programs that prisons officials say reduce recidivism.