Premier Dalton McGuinty’s decision to pull the plug on two power plants west of Toronto has come back to haunt him, with the Speaker ruling that MPPs have a right to view all government documents related to the projects.

Speaker Dave Levac ruled on Thursday that there is evidence Energy Minister Chris Bentley breached his privileges by refusing to release the documents to a legislative committee. The legislature could find Mr. Bentley in contempt of Parliament if he does not reveal all costs of the Liberals’ mid-campaign decision last September to halt construction of a gas-fired electricity plant in Mississauga and cancel another plant in Oakville a year earlier. Such a ruling would be unprecedented in 140 years in Ontario.

He has until Sept. 24 to comply.

“He’s been found guilty in the court of public opinion,” said Progressive Conservative Leader Tim Hudak.

Liberal House Leader John Milloy hinted that the government will resist handing over the information on the grounds that it is commercially sensitive, saying there has to be “some common sense around which documents can be produced.”

Opposition members called on Mr. Bentley to release the documents immediately. “What’s in those documents that you’re afraid of? What are you hiding?” Progressive Conservative MPP Rob Leone said in Question Period. “Does the word ‘contempt’ not bother you?”

Mr. McGuinty has acknowledged that he made the decision to scrap the controversial Mississauga power plant, which helped save four Liberal seats in the provincial election. The government says taxpayers are on the hook $190-million for the cancellation, but opposition members believe there are other costs. The government has not disclosed the tab for abandoning a power plant in the affluent enclave of Oakville.

“The public has a right to know how much the Liberal Party spent for their own election fortunes,” New Democrat Leader Andrea Horwath said.

The Speaker was asked for a ruling after Mr. Bentley refused to comply with a legislative committee’s request last May for all government documents relating to the projects. The Speaker said the committee was “unquestionably” entitled to request the documents and the minister had an obligation to comply.

“I am therefore satisfied that a prima facie case of privilege has been established,” the ruling says.