The Supreme Court of Canada won't hear an appeal in the case of a Winnipeg man who alleges his city's mayor violated provincial conflict-of-interest laws.

Mayor Sam Katz came under fire for hosting a $3,000 Christmas party in December 2010 for city councillors and staff at an Asian restaurant he owned.

Joe Chan, owner of another restaurant, asked the courts to find that Katz had broken the law and used his influence to have public money spent at his establishment.

A lower court ruled that Katz did not book the event at his establishment, and found no evidence he pressured city staff to do so.

The Manitoba Court of Appeal upheld that finding, as well as a ruling that ordered Chan to pay Katz $10,000 in legal costs.

As usual, the Supreme Court gave no reasons for refusing to hear the case.