This entry is rough to parse out because I barely know what you are talking about. It is not about your life and has limited context, so it is difficult to get my hooks in.
Ms. Fifteen Year old would be captured and returned to her parents ASAP and anyone near her would be charges with kidnapping and contributing to the delinquency of a minor.
If your parents are friend with the chief of police, even if you ARE 17, they will probably try to charge anyone around you (say... a blond boyfriend) with everything they can. They can't actually DO it, of course. But they can charge said boy.
Hypothetically.
Ah, but what you are dancing around here is familiar.
When Kate and you were dating, she ran away once. (She ran away a couple of times, but this one was the most serious length of having run away. This is also omitting the few nights when she would sneak out of her house and visit you--not because she wanted to be with you exactly but because she didn't want to be home.) She was seventeen, as you did not know her much before that point, and thus a legal enough adult in the eyes of the state of New York. The police could not force her to return to her parents' home, which they knew. This did not mean that they didn't try to apply whatever pressure they could on you, as the boyfriend. Clearly, you knew where Kate was--which you often but not always did.
She was still attending high school and taking her vitamins, as it were. She visited you on occasion, though far less time than both her parents and the police assumed. You may have been her way station the first night until she found other accommodations.
The police may have marked her car as stolen, which would have been ridiculous. It was Kate's car by rights, but her parents had paid for enough of it that it was theirs if they wanted to call it grand theft auto. (In my experience working in the justice system, it is a terrible idea to ever use the police against your child. I've taught the sons of mothers wanted to prove a point and then found that the police wouldn't let go. If you say your child committed a crime against you, that makes them a criminal to the police. Criminals go to juvenile detention.)
I don't remember the grievance that provoked this. Kate and her parents had friction going back to her early teens, so I cannot pinpoint one thing that set her off that time. All you knew was that she had run away, and it was now your duty to make sure that she survived the experience.
She crashed with a friend of hers whose parents had both tragically died, leaving him with both their life insurance payouts. (I don't remember what his name was, but he looked like Eliot Smith.) He had his own apartment in Poughkeepsie, though it was not in the nicest area. Nothing more than light recreational drug use occurred there during her tenure as houseguest. She will tell you a year later that she thought they might kiss and didn't. I cannot promise that it was the most wholesome situation, but he wasn't trying to leverage it. He was behaving as a good friend who happened to have a couch free.
Kate's parents made clear to your parents that, if you did not promptly return Kate, they would charge you with kidnapping and more serious crimes if that didn't work. Kate and you were both the age of consent in New York, but they wanted Kate back badly enough to make the threat.
They threatened to bring your parents up on charges for raising such a hooligan as you. You know, the high honor student who read and wrote, who started an improv troupe in high school, who did not drink or smoke, whose only arguable vice was mutual sexual contact with their daughter. It was only because your parents liked Kate that this didn't become a bigger issue. Though I do remember them drawing a line in the sand that they did not ever want to deal with Kate's parents. If Kate's parents showed up on their doorstep again, they would have discouraged you from continuing your relationship.
You wanted Kate to return home as because this situation was stressful for all concerned. That first weekend, Kate went to work with you so someone could pick her up from the mall. She then asked for money to buy supplies to live, since she left with barely more than the clothes on her back. There went your paycheck for a couple of weeks, but she was okay. You liked that you could provide for her, even if it were nothing more than toothpaste and shampoo.
Her parents had the police call you at work, directly threatening you this time. (The Children's Museum was not thrilled that the police were calling.) I don't remember if this was more about the false charges, but the officer made clear that he would trump up some reason to arrest you. You could only imagine that he would send a cruiser to arrest the guy who was nice enough to give her a place to stay. You, in short, were not going to tell some pig where your girlfriend was. You got off the phone and dialed her parents to talk about getting her home.
Of course, the officer was calling from their house and chewed you out for trying to tell them and not him. They were her parents. He was a guy threatening you with his eager abuse of institutional violence. Why would you be less than tight-lipped? His yelling at you seemed particularly rude given that you were calling to tell her parents where she was. It wasn't as though this were some brilliant tactic. If they had called instead of him, you would have told them where she was, but it was never about asking. It was about bringing you to heel, which was maybe a part of why Kate ran away. She had been brought to heel one too many times.
Your parents were never much for trying to punish you in that way, because you rarely did anything worth punishing. You couldn't process people behaving this way. Threatening you made you cower and close off. "Hey, Thomm, we are worried about Kate. We would like her to come home. Could you please talk to her for us and encourage her to make contact?" would have worked so much better with you. Express concern and sincerity and then let your guilt (and irritation at the inconvenience) do the rest.
Somehow, you managed to have a relationship with her parents after this. Somehow, they forgave you for taking care of their daughter while she was being rash and adolescent.
I think she was gone for two weeks, but I am willing to believe it was shorter than this or longer.