This morning I was in line at McDonalds behind a sheriff's van. The cover for the gas tank was still open. I thought about jumping out and telling him, or just closing it, but then I thought of that video I saw this morning of that pair of thugs making their "traffic stop" and thought better of it.
True story. I didn't want a gun pointed at me for approaching his vehicle.
Oh yea, that was a good choice indeed. They will think you loosened the cap and arrest you more likely than not IMO.