Halloween prank, could we get away with this?

I just moved into a very large community of townhouse condos so I'm expecting tons of trick or treaters.

I am also having quite a few people over halloween night, like a halloween party/house warming if you will.

So suppose that we got this prank going where I leave open the bedroom window that is right above my front door.

Then every time we get trick or treaters someone goes up there and pours a bottle of beer all over the kids and their parents.

But since the light in that room will be left off, if the parents can see anything at all, it will just be a hand holding a beer and they will never be able to describe/identify the person behind the hand.

Then if the police start getting calls about this and they show up at my house, we all just shrug our shoulders and say "Well gosh, we're sorry about that, but unfortunately we don't know who did it. You see, several people have been up there to use the hall bathroom and quite frankly it could have been anyone. Officer, I had no idea that this was going on in my home right under my nose, and for that I make a thousand apologies."

And what are the cops gonna do? We all have our fingerprints on one beer bottle or another and they can't identify exactly who was behind it.

So is there anything they can do besides say "Well make sure it doesn't happen again" and leave?

PS: No, I cannot be "evicted." These are condos, not apartments. I own my unit, pay a mortgage, not a lease.

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