AUGUSTA — If all 15 county jails in Maine capped their inmate populations at levels that would leave room for flexibility and surges in arrests, the entire statewide system would run out of space, a federal Department of Justice analyst warned Tuesday.

“If you do that, you’re not going to have enough beds,” said Rod Miller, who is working on an official report for the Justice Department’s Bureau of Justice Assistance.

Even if every jail in Maine was at full capacity, including newer jails in Somerset, Cumberland and York counties, space would be too tight, Miller said.

The expert met Tuesday with the state Board of Corrections’ Working Group. In recent weeks, he has met with people from every Maine county and toured almost every jail.

Currently, the state has about 1,800 people in its county jails. Yet, the state Board of Corrections officially lists its capacity at 2,315 beds.

That capacity, which includes every county cell, bunk and holding area in the system, is grossly inflated, Miller said. Jails cannot operate at 100 percent. They need room to house people where they belong, whether they are men or women, deserving of classification as a high security risk or can be trusted to behave without constant supervision.

The threshold is typically called “functional capacity.”

Maine’s county corrections network ought to send inmates to jails only until the threshold is reached, leaving any additional admittance up to the individual county’s jail administrator or sheriff, Miller said.

Had the state not formed its network of jails in 2009, more counties would be building new jails or exploring other alternatives to full cellblocks, he said. One alternative might be the creation of more halfway-style programs as an alternative to jail time, he said.

“Maybe we need to shift some people out of these jails,” Miller said.

Today, the system is not working, he said.

Maine’s jails are aging quickly and suffering from too little maintenance, he said. Morale among corrections officers is sinking. And cuts in programs aimed at educating inmates or getting them to kick drug habits are reducing some jails to warehouses.

All are aimed at meeting a bottom line in state spending on the jails that is too low, he said.

“You’re forced to do things that are going to make things worse over time,” he said. “The risk level gets worse and worse.”

He highlighted three jails — Penobscot in Bangor, Aroostook in Houlton and Androscoggin in Auburn — as particularly pinched by the new system. The jails in Bangor and Houlton are both overcrowded and the Auburn jail is teetering on its edge.

Currently, the state lists the Androscoggin County Jail’s capacity at 174 and budgets for a capacity of 160. However, local officials have set its functional capacity at 144.

On Tuesday morning, its population was 159.

Androscoggin County Sheriff Guy Desjardins was still accepting inmates from his own county, which is mandated by statute, but he was turning away inmates from elsewhere.

When Miller issues his written report — expected at the end of May — he will be listing his own estimates for the functional capacity of all Maine jails. His capacity for Androscoggin is likely to be even lower than the one set by Desjardins and Jail Administrator John Lebel.

Miller insisted that the 23-year-old Auburn jail was never meant to hold so many. It was originally designed to hold 117 inmates. Over the years, classrooms that were designed to serve as temporary dormitories became permanent cellblocks. Bunks were added to cells. State ratings on the facility crept up.

Miller was uncertain what the functional capacity ought to be.

He also stopped short of calling for a change in mission for any of the county jails, including the Oxford and Franklin facilities in Paris and Farmington, respectively. When the state network was formed, they were reclassified as 72-hour holding facilities.

Their longer-term inmates were sent to other counties.

“The justice system works differently for those guys and not better,” Miller said.

Too many inmates are being transported to other counties, making it tougher for inmates to stay connected with their families and communities, he said.

By law, inmates can be transported throughout Maine, but it can be costly for sheriffs departments and the courts, he said.

The Board of Corrections Working Group has endorsed the Franklin County initiative to restore its county jail.

A public hearing on the matter is scheduled for 4 p.m. June 12 in the North Dining Hall of the University of Maine at Farmington.

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