Dear Prudence: One of my best friends went through a rough patch a few months ago and used substances (both legal and illegal) to cope, eventually resulting in a DWI.

I live in a "party" city where I moved last year for a job. She and a mutual friend expressed interest in coming to visit, and she told me she was getting out of probation early. She's been having money trouble so I bought her plane ticket. They came, they partied, and they spent most nights blackout drunk despite my talking to them about their behavior. It would be an embarrassing and regret-filled weekend, if they could remember.

I found out after she left that she had not gotten off probation early (in fact her probation was twice as long as she had revealed), or told her officer she would be leaving the state. She also was not supposed to be drinking while on probation. I now feel like an accomplice to her crimes, especially because I purchased the ticket, but also because I now know she really needs more help and supervision.

Neither her parents nor our friends see this as an issue. Should I contact her probation officer anonymously and tell her what happened (I have Facebook photos to prove it), try to get her help in some way, or sweep it under the rug like everyone else?

Prudence says: The drunken driver who recently killed two people and plowed into two dozen others at the South by Southwest festival had a previous DWI conviction. I wonder if his friends are now wishing they had done more to stop him.

Your friend lied to you and made you party to a parole violation. She also made you party to her nonstop partying. It must have been lovely to catch up with her while holding her hair away from the vomit. She has amply demonstrated that she's a danger to herself and others, and it's the others I'm most concerned about.

It's very sad for a young person to let her life be ruined by alcohol, but it's even worse if she's going to also endanger innocent people. It's astounding that her parents aren't alarmed by her current condition and what lies down the road if she doesn't stop. But maybe having oblivious parents is a source of some of her troubles.

One thing I learn over and over again in this column is how difficult — and sometimes impossible — it is to save someone else. But you have an unusual opportunity to force your friend to address her problems. So I encourage you to contact your friend's parole officer and tell her what went on. It's true this could possibly land your friend back in jail, but at least there she'll be sober. The result could also be that she is required to go to rehab or get more serious monitoring. Let's hope that this time when the criminal justice system acts, your friend finally comes to see that gravity of the choices facing her.

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