Conflict of Interest and Ethics Commissioner Mary Dawson says Hill breached Sec. 33 of the act, which prohibits former public office holders from taking improper advantage of their previous office.
Hill contacted cabinet ministers in 2011 about an impending oilpatch deal between Progress Energy and Malaysian oil giant Petronas to share the ownership and development of three shale gas sites in northeastern British Columbia, and to export natural gas to Malaysia.
At the time, Hill's wife Leah Murray worked for National Public Relations, a firm that had drafted a communications plan for the deal.
The report says Hill, who left politics in 2010, used his former position to "facilitate access" to the ministers on behalf of his spouse and her employer.
During the investigation, Hill maintained that he only wanted to give his former colleagues a heads-up about the impending multi-million dollar deal.
But Dawson disputed that claim in her report.
"Mr. Hill described these calls to the ministers as simple heads-up calls," she wrote.
"The evidence, however, shows that he went further. (International Trade) Minister (Ed) Fast told me that Mr. Hill had requested that he call Progress Energy."
Dawson also pointed to other evidence, including testimony from Industry Minister Christian Paradis, who said Hill suggested that he, too, call the company.
And although witness testimony differed slightly, Dawson concluded that Hill’s calls were intended to assist his spouse in carrying out one of the steps identified in the strategic communications plan developed by her employer.
"His calls increased the likelihood that Ms. Murray and her employer would succeed in implementing some of the objectives of the strategic communications plan," Dawson's report said.
"Mr. Hill therefore acted in a manner as to take improper advantage of his previous public office as leader of the government in the House of Commons, and thereby contravened section 33."
Hill, having been the House Leader for the Conservatives in the House of Commons, would have known the ethics rules inside and out, said NDP ethics critic Charlie Angus.
"We have someone who would have known better . . . giving a heads up to inside Conservatives," said Angus.
"It really seems that the prime minister has no standard, has no ethical bar. This is just one other example of the Conservatives breaking the rules."
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