The Gwinnett County Jail is overcrowded again, even though 360 beds are going unused.

Gwinnett Sheriff Butch Conway says a lack of manpower prevents him from opening six housing units that could hold more inmates. Instead, he is triple-bunking about 400 inmates and housing others at a jail in Pelham.

The unused housing units are part of a $78 million jail tower expansion that was completed in 2006 and paid for with a voter-approved bond. The expansion added 1,440 beds and was supposed to alleviate overcrowding for years to come.

Conway said he is trying to avoid opening that part of the new tower because he would have to hire 30 more deputies or pay more overtime to staff it.

"It's a matter of economy, what we can get from commissioners and what they have to give us," Conway said. "We're trying to work with them."

The commission in 2006 approved the hiring of 79 deputies to staff the expanded jail. However, more deputies are needed now to manage an average daily inmate population that has swelled from 2,281 to 2,686 over the past four years, the sheriff's office said.

At the same time, there has been an increased demand for deputies to provide security at the courthouse and in jail courtrooms, which are operating at full capacity, said the sheriff's spokeswoman, Stacey Bourbonnais.

The commissioners turned down a request last year to hire 30 more deputies, even though they raised the sheriff's budget from $66.3 million to $66.9 million. Other county departments saw their budgets cut by a total of $380 million last year.

Conway said he will renew his request for 30 deputy positions and an additional five supervisory positions in the 2011 budget, which will be voted on in January.

County government spokesman Joe Sorenson declined Tuesday to comment about how the sheriff is managing his resources. Sorenson said no decisions have been made yet about the 2011 budget, but a declining tax digest is likely to mean some county departments will have to tighten their belt.

"There's never been enough money to fill all the requests from all the different agencies, and in 2011 we know there is going to be less money," Sorenson said.

In the meantime, the triple-bunked inmates sleep on makeshift beds on the floor in cells designed for two. The arrangement is not only less comfortable for inmates, it is also less safe.

"It is taxing for the deputy who has to monitor that many inmates and it raises tensions in the cells and units," Bourbonnais said.

To free up space, the sheriff last month began housing out about half of the 211 state-sentenced inmates who are awaiting transfer to the state prison system. Ninety-two prisoners were sent to the city jail in Pelham at a rate of $22.50 per inmate per day. That's the same rate at which the state reimburses Gwinnett for keeping state prisoners, Conway said.

The sheriff has another option that would free up employees to staff the unused housing units. But it's an option Conway said he doesn't want to consider: He could reassign some of the 18 deputies who are trained to identify illegal immigrants in the jail for possible deportation.

The controversial program, known as 287(g), is a local-federal partnership with Immigration and Customs Enforcement. The Gwinnett County Sheriff's Department is one of 66 law enforcement agencies nationwide and five in Georgia that participate.

Pro-immigrant groups who oppose 287(g) have called for the program to be axed. They say it erodes trust between immigrant communities and law enforcement.

“It is unfortunate that the sheriff insists on continuing the county’s involvement in the failed 287(g) program, despite the demonstrated derailment of scarce resources and the significant burden it puts on law enforcement in Gwinnett," said Azadeh Shahshahani, a spokeswoman for the American Civil Liberties Union of Georgia.

Sabrina Smith, who chairs a nonpartisan group called Gwinnett Citizens for Responsible Government, backs the sheriff's decision to devote 18 deputies to screening for illegal immigrants. However, she is concerned the county could face lawsuits due to inmate overcrowding.

"Sheriff Conway is in a position of almost damned if you do, damned if you don't," Smith said. "The taxpayers unfortunately are the ones that end up having to pay either way."

Conway believes weeding out illegal immigrants will get rid of some repeat offenders, eventually reducing the overall jail population and forestalling a need for a second jail expansion. About 20 percent of Gwinnett inmates are illegal immigrants, Conway said.

"Hopefully an effect of 287(g) -- aside from sending people outside the country that shouldn't be here -- is to keep our [jail] population from annual increases we've seen for years," Conway said.