The state government has called for developers to tender for the construction of the Kalgoorlie Courthouse.
The construction is part of a $43 million redevelopment of court facilities in the Goldfields, some of which are located in heritage-listed buildings.
"As local residents will have seen, the exterior restoration of the heritage-listed Government Office Building, including the old Post Office and Warden's Court is already well under way," Attorney General Christian Porter said.
"This tender is for the new annexe to the rear of the site, including a secure overhead footbridge to transfer persons in custody from the police lockup to the courthouse.
"Also included in the tender are the more public functions of the courthouse, including the registry, in the heritage building facing Hannan Street."
The new facility will comprise four courtrooms, with the potential to expand to five courts when required.
The tender is expected to be awarded in June, with work beginning in July.
The complex is scheduled to be completed by mid-2013.