Yes, unlucky mate but they can yellow sticker you whenever they feel like it! My brother hopped out his car at the beach and they called him back to award him a canary. The only time you can stop this happening is if you've parked in a garage with the door already down before they arrive, which then you can request they get a search warrant before you let them enter your property. But let's face it, they'll be back in 10 with the warrant and twice as pissed off as they were before. Sorry so say the cops can pretty much do what they like.