Tinsley's letter did not cite any court order as grounds for withholding the subpoenas.
McGinley pointed out that in recent months, Toyota has disclosed details of subpoenas it has received in a federal grand jury investigation into the safety of the company's vehicles.
Several years ago in Illinois, lawyers for then-Gov. Rod Blagojevich cited the same federal rule that Tinsley did when they were trying to keep secret subpoenas served on Blagojevich's office.
In the case, the Chicago-based watchdog group Better Government Association had filed suit to make Blagojevich release the subpoenas.
A state appeals court held that federal rules on grand jury secrecy did not pre-empt Illinois' Freedom of Information Act. In its opinion, the court also noted that those rules do not prohibit private citizens who receive subpoenas from disclosing their contents.
Manchin is running for U.S. Senate in West Virginia's special election to replace the late Sen. Robert C. Byrd. His office has declined to elaborate on the nature of the subpoenas.
In a statement released earlier this month, the Manchin administration confirmed that the state received two subpoenas. It also said the state has not been advised that Manchin or any other state official is under investigation.
The subpoenas seek documents and were served on the two agencies, not individuals, Tinsley has previously said.
The Gazette has submitted another written request to Tinsley, urging him to reconsider his position.
Reach Alison Knezevich at alis...@wvgazette.com or 304-348-1240.