THORNTON — Two years after the Adams County Sheriff capped the number of municipal offenders who can be housed at the county jail, police chiefs from five cities said Tuesday the issue has become a threat to public safety.

Until now, the chiefs have been mostly quiet about their discontent and have not divulged details of negotiations over the past two years, but they say things changed when the sheriff’s department began to reject Aurora inmates last week.

“We believe this to be a crisis,” Aurora Police Chief Dan Oates said during a news conference with police chiefs from Brighton, Westminster, Thornton and Commerce City. “These folks belong in jail.”

In the past week, 19 people charged with municipal offenses in Aurora were sentenced to jail by municipal judges, Oates said.

Seven of them were rejected by the Adams County jail and are being held in Denver County. Aurora has a contract to house inmates that exceed Adams County’s cap in the Denver County jail and has spent more than $60,0000 in the past 18 months.

One of the inmates rejected last week was sentenced for motor vehicle theft. Oates said the man has five prior convictions, including for burglary and eluding police.

Collectively, Oates said the seven inmates blocked last week from serving jail time in Adams County have 36 prior felony convictions and 64 prior misdemeanor arrests.

The jail’s cap sets a limit of 30 municipal inmates on any given day. The 30 spots are shared among nine municipalities.

Budget cuts closed three housing units at the Adams County jail because there weren’t enough deputies to manage inmates. In late 2011, Sheriff Doug Darr proposed the cap as a remedy. It was approved by the Board of County Commissioners.

A new group of county commissioners in December approved a budget that included funding to bring levels up to full staffing and allocated money for overhires at the jail — a hiring strategy to hire and train employees in anticipation of future vacancies.

After a report by the Criminal Justice Coordinating Committee concluded that increasing the sheriff’s hiring budget would make more beds available to municipal inmates, the commissioners in April passed a resolution to repeal the jail cap.

Darr, however, has not abandoned the cap. On Tuesday, he declined to comment, saying he was preparing statements that he plans to release Wednesday.

The Brighton, Westminster, Thornton and Commerce City police chiefs said they are concerned their inmates could be rejected next.

“I have public-safety concerns for our residents and businesses,” Thornton Police Chief Randy Nelson said. “A great deal of efforts have already been made, not only with the police chiefs but with the judges, to look at the totality of this problem. But does the sheriff truly recognize this effort? I don’t believe he does. There has to be an alternative.”

One idea the chiefs proposed Tuesday suggests drawing money set aside to hire deputies to cover the cost of jailing municipal inmates elsewhere.

“We’re frankly returning to the court of public opinion because all the other vehicles that we in government have tried … haven’t worked,” Oates said.

Yesenia Robles: 303-954-1372, yrobles@denverpost.com or twitter.com/yeseniarobles

Correction: This online archive has been altered to clarify the conclusions of the Criminal Justice Coordinating Committee.