The government signalled in the budget last week that it would amend legislation to require the government to submit preliminary ads for the auditor general to review, define "partisan" in relation to its advertising and restrict government ads during elections.
Auditor General Bonnie Lysyk said the proposed changes would "gut" the 10-year-old act.
They would place her office "in the untenable and unacceptable position of approving ads because they conform to the narrow requirements of the amended government advertising act, but may be clearly partisan by any objective, reasonable standard," she said.
The Liberals want to define partisan by banning the use of an elected member's picture, name, voice or the colour or logo associated with the political party, she said.
"The government could run TV commercials with ordinary Ontarians saying, 'This government has introduced great policies on health, on environment, on jobs. This government gets us, but the other guys don't,'" Lysyk said.
"Under the proposed amendments such an ad would no longer be considered partisan, although most reasonable people would conclude otherwise, yet it is Ontario taxpayers who would have paid for them."
In the past 10 years the auditor general has reviewed more than 7,200 ads worth over $400 million and has rejected less than one per cent, she said.
Lysyk said she would be outlining her concerns in detail to the Speaker. If the proposed amendments stay, she will ask the government to remove the auditor general's responsibility to review advertising altogether, Lysyk said.
Deb Matthews, the president of the Treasury Board, said if Lysyk has amendments to suggest, they should discuss them. Matthews said Liberal government advertising has been rejected or changes forced in the past due to too much red, for example on bricks and apples. Lysyk said that has not happened during her tenure as auditor general.
Progressive Conservative Steve Clark suggested the changes were buried in the budget bill, as his party was not aware of them until Lysyk spoke up Wednesday.
New Democrat Gilles Bisson said if the changes go through, provincial government ads will start looking like much-criticized federal Conservative ones.
"Here we've got Premier (Kathleen) Wynne, who's always railing against how Stephen Harper is the worst thing since sliced bread...All of a sudden here she is mimicking her rules when it comes to advertising," he said.
The Harper government has booked $13.5 million for an all-out, co-ordinated blitz in April and May to advertise its 2015 pre-election budget. It comes amid increasingly vocal opposition to the government's use of taxpayer-funded advertising.
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