The Otay Mesa detention center near San Diego is operated by Corrections Corporation of America, under contract with Immigration and Customs Enforcement. CCA is one of the largest private prison company in the country. (The Washington Post)

The Department of Homeland Security on Monday said it would reexamine the use of private operators for detention facilities, signaling a potentially major change in U.S. immigration policy.

Secretary Jeh Johnson said in a statement that he has asked the Homeland Security Advisory Council to evaluate whether the use of private immigrant detention “should be eliminated.” He said the review will be finished within three months.

The move highlights how the government is considering a broad pullback from contracting with for-profit companies after decades of reliance on the operators for its immigration facilities and its federal prisons. Earlier this month, the Justice Department said it would gradually close its 13 private prisons, calling them both less safe and less effective than those run by the government. Johnson said Monday that the advisory council should look at whether to “move in the same direction,” considering “all factors,” including cost.

The U.S. Immigration and Customs Enforcement agency — a component of DHS — holds more than 60 percent of its 400,000 annual detainees at private facilities. Nine of the 10 largest detention centers are private, operated either by the Corrections Corp. of America or the GEO Group. The facilities hold individuals who have committed crimes, are awaiting deportation or are pressing legal claims to remain in the country. In 2014, both companies were also awarded contracts to house mother and child asylum seekers; the deals are unusual because the firms receive fixed payments no matter how many beds are occupied.

If the federal government eliminates or reduces the use of private facilities, it would be forced to undertake a major transition, either by building its own immigration facilities, placing more detainees in state and local facilities or reducing the number of immigrants being held.

Both major private operators saw their shares skid more than 3 percent following the DHS announcement. CCA in 2015 received 24 percent of its revenue from ICE, compared with 18 percent for GEO. CCA’s stock, at $32.54 per share at the beginning of the month, on Monday tumbled below $17.

Greg Chen, director of advocacy for the American Immigration Lawyers Association, said that the government has for years overused immigration detention, neglecting cheaper alternatives like ankle monitors for those awaiting legal cases.

“The fact is, DOJ has long been reexamining the use of incarceration, and this has been developing for years, and immigration authorities have been much slower to consider methods other than jails,” Chen said. “The use of private detention is not necessary.”

CCA, in a statement, said it was “proud of the quality and value of the services we provide” and would share information with Judge William Webster, chairman of the DHS advisory council.

“We’ve worked with the federal government to provide solutions to pressing immigration challenges for more than 30 years, and we welcome this review of our long-standing relationship,” the company said. “This effort builds on the unfettered, daily, onsite access ICE officials have to our facilities and the thousands of government audits we’re subject to each year.”

GEO, in a statement, said its immigration facilities are “highly rated and provide high-quality, cost-effective services in safe, secure, and humane residential environments pursuant to strict contractual requirements and the Federal Government’s national standards.” GEO said that in recent audits, all of its facilities were found to be in compliance.