>>3810452They're not gonna do anything. are they C-41 or B&W ? honestly if it's BW, just dev yourself. But for a party I really wouldn't worry. not only it isn't worth the trouble for the lab but I suspect for the police also and it wouldn't be good for business if they ratted every single slightly illegal activity captured on film.
If you're still worried, just ask for a dev without scans or enlargement. they're not going to go comb through your negs to see if any illegal shit is happening.