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Mugyenyi, they say, is a proxy candidate. She acknowledged that she decided to run after her husband, Yves Engler, was denied entry into the race. The committee argued that this constituted a breach of “honesty, professionalism and integrity” and therefore disqualified her.
From https://www.cbc.ca/news/politics/yves-engler-barred-ndp-leadership-9.7010236
Among other reasons listed in the NDP decision not to allow Engler's candidacy are engaging in Rwandan genocide denialism, echoing Russian propaganda about the war in Ukraine and making comments "consistent with antisemitic attitudes."