Faking GPS location

[bontopia]

DD15 asked last minute to join us on holiday a day late so she could go to a party with friends from her sports club. We agreed because she studies hard and trains intensively so parties don't happen often and her older siblings were also coming later from sport camps. On returning home we've worked out the party took place at our house (too tidy!) and that she downloaded GPS hiding software that afternoon and sent us a fake location when I checked in with her that night. We're not in the uk and it's quite normal here for parents to leave teens her age for the night. We've let her stay home before and have a friend over, but now she's betrayed our trust. I'd appreciate thoughts on how you'd handle this.

So your house ended up tidier than it started? Party on, DD.

Honestly, I’d ostrich, and not say anything for now. But I would be wary of leaving my DD again. Parties have a nasty habit of getting out of hand.

Well. There's no damage and they've tidied which is pretty good going. My concern would be to know what precautions they put in place if someone needed the emergency services.

To be honest I'd be really pissed off about the lying. Can you explain that to her? Would she really get it.

It sounds like she's a really good kid. What would you have done if an elder sibling had done the same thing at her age or even now. Is it her age that annoys you or the lying? A mix of both? Would you have said yes if asked?

I'm very impressed that your deduction that the party took place at your own house was only based on the fact that the place is too tidy! For most similar situations you would have worked it out from empty beercans and other detritus stashed in places that an inefficient hangover-clean failed to find. How sure are you that no valuables are missing?

If there's no physical damage then obviously the breech of trust remains. It's important that the scope and type of consequences follow the scope and type of the wrongdoing. So maybe it goes something like:

We are impressed that your efforts to hide the fact that you had a party were almost successful. That must have taken a lot of work. Now if you'd had a party with oir permission and the place got trashed, the consequences would have been extra chores to pay off the extra work that was needed to set things straight. But just because everything got tidied and clean doesn't mean there's no harm done. You've broken our trust, and the consequence of that is that you don't get trusted for a while, until there's an opportunity for you to start rebuilding trust.

Then you need to follow through and make her life less convenient and less independent because you aren't trusting her to be as mature and capable as she could be. This will probably be a pain for you too so any knock-on consequences can also be loaded on to her e.g. We couldn't trust you to (x) so I had to (y) and that means I don't have time for (z) which means you have to sort out (z) without me.

Are these facts that you know it was there and she's stated so or just suspicious solely due to the tidiness aspect?

Have you seen the faking GPS signal app on her phone or history?

One of the joys of growing up is doing stuff like this. It actually sounds like you are doing well in teaching her independence. She sounds pretty sensible so I would make a pointed comment that she did not pull the wool over your eyes, that you know everything that went on and in future she should be more honest with you. But I would not punish her as it sounds like she had everything under control.
Then again I am not one for punishing misdemeanours or creating artificial consequences.

Thanks for all the comments, really useful as I was expecting that hefty punishment would be advised! The tidiness led me to check the dustbin which showed proof and I can see that she downloaded the faking app.
I would have said no if she'd asked this time as it was only a few hours before we were due to leave. But she's 16 soon and then with planning and ground rules it would be ok.
I'll follow the suggestions to make clear how annoyed we are about the lying and give her a bit less independence until she has won back trust.