PORTLAND, Maine — Gov. Paul LePage is moving forward with plans to build a psychiatric home that would be privately managed, circumventing lawmakers who are calling for legislative oversight.

Although the facility would be built on state land, the state would sell it to the construction company, Cianbro, then lease back the property to the state, Department of Administrative and Financial Services spokesman David Heidrich told The Associated Press on Thursday. A separate company would manage the facility.

The administration has estimated construction of the $3.5 million psychiatric residence could start next spring and end in March 2019.

LePage, lawmakers and advocates for the mentally ill agree the 21-bed facility will provide needed beds for patients in state custody at Riverview Psychiatric Center who faced criminal charges and no longer need hospital care. The administration also has said the facility could help regain Riverview’s federal certification at a time when the federal government is demanding Maine return $51 million it spent at Riverview.

Democratic Attorney General Janet Mills said earlier this year lawmakers who make up the Legislative Council would need to approve the residence if it was to be built in Augusta, as originally planned. The Republican governor said repetitive questions from lawmakers slowed down the process, so he instead decided to build the facility in Bangor, which does not require Legislative Council approval. The site is down the road from the state-owned Dorothea Dix Psychiatric Center.

“It is this miserable record that forces me to do everything in my power to remove the Legislature from this process,” LePage told lawmakers in a January letter.

Mills and the ACLU of Maine said the Legislature’s approval still is needed to construct a new state building outside Augusta.

“This is really uncharted territory for the state of Maine,” Democratic state Rep. Drew Gattine, co-chair of the Legislature’s appropriations and financial affairs committee, said. “The state has been taking care of these patients for decades, maybe for even over a century.”

The administration plans to select a company to run the facility. The Department of Health and Human Services said it will use unspent funds for the facility but did not provide a detailed breakdown.

The ACLU has argued the department can’t use existing funds for a new program.

LePage this month vetoed Gattine’s bill that would have required the state to operate the facility and build it in Augusta. The governor said the bill would significantly disrupt a plan “well underway.”

“Additionally, this bill would require the secure forensic rehabilitation facility to be operated by the state, growing state government at a significantly increased cost to Maine’s taxpayers,” LePage said.

Gattine’s bill received support from Democrats and several Senate Republicans but lacked enough House support to override the veto.