The ATA is the teacher's union, they invited a literal murderer to speak at a conference: https://nationalpost.com/news/canada/alberta-teachers-association-defends-murderer-speaking-at-calgary-conference

The Calgary City Teachers’ Convention, scheduled for Feb. 14 and 15, had billed Evans as someone who’s familiar with the struggles of addiction, and says his “message is one of hope,” having “the lived experience of active addiction and active recovery.”