McGuinty signed on to the Ontario lobbyist registry in August — 18 months after he left office following a decade as premier — to act on behalf of Kitchener-based Desire2Learn, which develops educational software.
"I want schools everywhere, and especially our own schools, to use D2L products because that creates Ontario jobs," McGuinty said in a statement.
Desire2Learn has been getting Ontario government contracts since 2006, and last year did more than $3 million worth of business with the province.
The company "is better than anybody else" at making technology that supports the latest thinking about how to improve student learning, added McGuinty.
"I am proud to be representing Desire2Learn before the Ontario government as well as all other governments and businesses around the world," he said.
Liberal cabinet ministers heading into a meeting Wednesday said McGuinty had followed the rules, which require that he wait one year before lobbying his former cabinet colleagues.
Treasury Board President Deb Matthews said the key for her is transparency, and noted McGuinty has made his lobbying efforts completely public.
"Do people know that he's lobbying? Yes they do know, so I think there will be a scrutiny on those interactions because people know," said Matthews.
Education Minister Liz Sandals gently scolded reporters who suggested McGuinty should not lobby on behalf of a company that received millions of dollars in provincial government contracts when he was premier.
"Just a minute, just a minute," said Sandals.
"To the best of my knowledge he has followed the rules, and by definition any topic that he would lobby on in Ontario where there was a prior existing funding relationship would have been when he was premier."
The NDP wants politicians to wait five years before they lobby their former colleagues — the same time period federal MPs have to wait — to stop what they call the "revolving door" from the premier's office to a lobbyist's office.
"New Democrats have serious concerns with Dalton McGuinty lobbying for a private company when just over a year ago he was in the premier's chair," said NDP critic Cindy Forster.
"When it comes to cooling-off periods, even Stephen Harper has stronger rules than (premier) Kathleen Wynne."
Ontario's Progressive Conservatives declined to comment on McGuinty's new role as a lobbyist.
McGuinty said he contacted the Integrity Commissioner about his "part-time role as a senior adviser" to Desire2Learn out of an abundance of caution after he arranged a briefing between the company and education ministry officials.
The New Democrats said they were "shocked" the Liberals didn't have a problem with McGuinty becoming a lobbyist so soon after leaving office.
"It makes it a bit rich for the Liberals to brag about accountability," said Forster.
Matthews, who is responsible for provincial accountability legislation, said the Ontario government doesn't plan to increase the one-year ban on lobbying by former members of the legislature.
"I don't see the need to do that," she said. "There's a cooling off period now that has a real impact on people, so as long as we're open and transparent about it ... I think we're in good shape."
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