HELENA, Mont. — The Montana Department of Corrections is breaking the law by housing youth and adult offenders in the same facility and by contracting to send girl offenders to a youth prison in Idaho, a recently released audit found.

Corrections director Mike Batista said he disagreed with the findings of the Legislative Audit Division, and the low inmate populations at the Pine Hills and Riverside youth correctional facilities required department officials to take action to maximize resources.

The Legislative Audit Committee is set to take up the report on Thursday.

Over the past year, the department has started placing adult offenders at both the 72-bed Pine Hills prison for boys in Miles City and the 20-bed Riverside prison for girls in Boulder.

The rising adult inmate population created the need for additional housing, while the decreasing juvenile inmate population created space at the two youth facilities, according to the audit.

However, state law prohibits the department from placing youths in facilities where adult offenders are carrying out their sentences, the auditors wrote.

In the case of Pine Hills, department officials followed federal regulations that require youth offenders to be separated from adult offenders by sight and sound. But Montana law states explicitly that youth and adult offenders can’t be housed in the same facility at all, the auditors wrote.

As of Monday, there were 39 youths and 13 adults housed at Pine Hills, according to the department’s prison population report.

In Riverside, the department contracted with 5-C Juvenile Detention Center earlier this year to place girl offenders in a prison in St. Anthony, Idaho, freeing up the entire Montana facility for adult offenders. As of Monday, there were three girls listed as “off-site” on the department’s population report.

The auditors found the contract is in violation of state law. The department may only sign a contract for the placement and care of delinquent youth when the youth prison population is over capacity, or when the state doesn’t have an adequate facility, the report said.

The auditors recommended the department follow the law by using Pine Hills and Riverside as they were intended.

Batista wrote in response that along with the laws the audit cites, another state law requires that the department use its resources at maximum efficiency. The department decided to follow that law because of the low youth offender population, excess capacity in those prisons and because of the rising cost of care.

“The department carefully performed its due diligence before making changes to the uses and population compositions of the Pine Hills and Riverside correctional facilities,” he wrote.

Batista acknowledged the laws conflict with each other in the department’s current situation but said they need to be reconciled through legislative action.

Corrections spokeswoman Judy Beck did not return a call for comment.