I kept threatening my mom that I would move out if she didn't let me do what I wanted (I was 17). Finally one day my mom marched into my room with a suitcase and started to pack my bags. Really opened up my eyes quick. Sounds like your daughter is using that as a "threat" believing that you will back down and let her do what she wants if she "threatens" you with leaving. My mom's words to me were (as she was packing my bag)... "You want to leave so bad? You think you have it horrible here and I'm such a bad person cos I won't let you run around whereever you want, take my car whenever you want? Here let me help you". When I knew she wouldn't put up with the bull I was giving her I backed down. Mom told me its her house, her rules, you can go out with your friends, but as long as you live in this house you will do follow the rules. She wanted to know where I was because she loved me and wanted to know I was safe. That is what she told me. She said that when I turn 18 I will be of legal age and if I want to move out she will help me find a place that I can support myself on. But until then I had to respect her as much as she respected me. I had a curfue. Midnight on weekends, 11 pm on school nights. As for the drinking thing...its not okay...it is illegal. There are laws and they should be followed. Under age drinking is illegal, robbery is illegal, speeding is illegal, etc, etc. There are many things that are illegal and for good reason. I worked with a lady who told me how responsible and wonderful and mature her son is. At 16 they bought him whatever kind of car he wanted, let him do what he wanted. "He's such a good person and we trust him totally. He tells us he doesn't drink or party or "hang out". He's always at the library or his friends studying. She came in one Monday in tears. That weekend the police had brought him home from a "party" where there were no adults. He was drunk and the police were called in because there was underage drinking.