Can someone with a misdemeanor be able to legally enter Canada from the U.S.?

A few years back my best friend Jeremy invited some of his minor friends to his 21st birthday party. A fight broke out between him, his gf, and another guy that his gf was cheating on Jeremy with. Some neighbors called the cops and Jeremy got busted with a bunch of misdemeanor offenses, including the corruption of minors, disturbing the peace, and simple assault. Is Jeremy banned from Canada now, or is that just for felons? Because I heard that U.S. citizens who have a criminal record aren't allowed to enter Canada? I just wanted to know, because I live near the Canadian border. I thought I'd do something crazy like explore Canada this summer and bring some friends.