SAN ANTONIO — As federal officials begin an overhaul of the widely criticized system used to incarcerate immigrants awaiting hearings and deportation, their challenge includes a deep inconsistency in the amount paid to a hastily assembled network of private prisons and local jails that hold thousands of such detainees.

Contracts obtained by The Associated Press illustrate the problem in paper-heavy detail, and not all of the discrepancies can be explained by geography or differences in the cost of living. For example, a suburban Atlanta county is paid less than $43 per day to house an illegal immigrant, while a rural New Mexico county gets $97 a day — just a few dollars shy of the amount paid for a bed in Los Angeles.

Some county jails charge only the actual cost of housing an immigrant, while others acknowledge partnering with private prison companies to profit from the system.

Last week, the Obama administration announced a series of "major reforms" in the detention of illegal immigrants, including placing federal employees inside the largest facilities to monitor detainee treatment. In doing so, John Morton, the new director of Immigration and Customs Enforcement, acknowledged the current system is both inconsistent and lacks oversight.

"There isn't a uniform rhyme or reason to it," he said.

Morton pledged to review all the agreements ICE has to detain illegal immigrants at 350 different facilities, an operation that will cost $1.7 billion this year. Most of the facilities were designed to hold criminals, but the immigrants detained by ICE face only civil immigration proceedings and many have never been convicted of any crime. They include families and people seeking asylum.

Only a tenth of the 33,400 beds in use are owned by ICE, and many of those beds are guarded by private contractors. An additional 16 percent of the beds in the ICE network are completely owned and operated by private prison companies. The majority of beds are owned by local and state governments, some of which outsource their jail and prison operations to private contractors.

The result is that in all but a handful of cases, the federal detention of an immigrant involves a payment to an outside company or agency.

Many of those contracts were negotiated over the last decade when the government was outsourcing a growing number of services and ICE, under pressure to detain more immigrants who had previously been allowed to remain free, was rushing to add space.

"They had to find quick places with beds," said Peter L. Markowitz, director of the Immigration Justice Clinic at the Benjamin N. Cardozo School of Law.

Through a Freedom of Information request, the AP obtained ICE's contracts with some of the largest immigration detention facilities; the agency also recently began posting dozens of other contracts online. The daily rate paid for a jail bed varies widely among 38 government-to-government agreements signed since 2006, even within the same regions.

For example, Orange County, N.Y., has a deal to house detainees for nearly $134 per day, compared with $105 per day in Monmouth County, N.J. Separated by 106 miles, the counties sit about the same distance from New York City.

The deals ICE signs with local governments allow for some profit, said agency spokeswoman Ernestine Fobbs. Haskell County, Texas, takes in about $1,000 per month more than it pays a private contractor to run its Rolling Plains Regional Detention Center, and the extra money is used to boost salaries in the three-man sheriff's department, said the county's top official, David Davis.

But at less than $58 per day, Haskell County receives far less than the $97 per immigrant being paid to Otero County, N.M., even though both counties are rural and built prisons as economic development projects. Davis said he wasn't aware that other counties were getting paid substantially more.

"I've never compared what we had with what they had," he said.

Otero County opened its immigration detention facility last year about 25 miles north of El Paso. Approached by a private contractor looking to arrange the deal, "the county saw a potential to increase some revenues," said Assistant County Manager Ray Backstom.

The county makes a "small" profit on every bed that's occupied, said Backstrom, though he wasn't sure how much. He said he wasn't directly involved in the negotiations between ICE, the county and Centerville, Utah-based Management and Training Corp., the private company that built and runs the facility. ICE pays Otero County about $3 less per immigrant per day than it pays Los Angeles County.

Morton said ICE has long-term plans to find arrangements that are more suitable than prison-like facilities. "We're going to focus on building a better mouse trap," he said.

Immigrant advocates say that could mean more use of electronic monitoring, allowing immigrants to remain free while pressing their cases in court. ICE officials have said that electronic surveillance programs that cost about $13 per day have a near perfect compliance rate, though they complain cases generally take longer to resolve when immigrants are free.

"There are entities that are profiting from the use of detention," said Jacqueline Esposito, policy coordinator for Detention Watch Network. "There are community-based alternatives and they cost a fraction of the price. You have to wonder then what the motivation is behind a detention system that has exploded."

On the Net: U.S. Immigration and Customs Enforcement: