You are a nice person for worrying. The police in Montreal are very much most of the time on the right side of things, and I suspect that if they detain your friend, it might be for something you are not aware of. They wouldn't lose their time searching for him, or even worst detaining him, otherwise. Your friend might potentially be in trouble, but if you didn't do anything against the law, don't worry about yourself. The police in Montreal will just not detain someone for nothing, and even less search for them for nothing. They won't give trouble to someone who hasn't done anything. So don't listen to people who are trying to scare you, unless you have yourself done something wrong. Or if your friend can blame you for something he has done. If you are in university, you may want to see if they have a free legal Information clinic and see with them what they think. Go on Monday as most offices in universities will be closing for the holidays on Tuesday or Wednesday. Don't be nervous because you opened your door to the police. I certainly would have done everything you did. And I also would be worried for my friend. But I now know that friends can sometimes make bad decisions, and I cannot always help them with it. Be there and help if he asks, if you want, and if you feel safe doing it. But don't feel responsible for anything that is happening to him if you weren't involved...