well yeah, i guessed that but I'm thinking of "MOT / friendly police man stopped me today" time.
just wondering if anyone knew if it was legal or not, just for the record 
they wont b visable when they r not turned on, my mate got pulled over t'uver day and the police man asked if he could c his neons turned on!!!! some people r strange!!!
I don't like the sound of that!
I was in a carpark once setting up my amp for my subs in a previous car, i don't like to do it at home as i don't want people to know what i got in the car. However, about 20 minutes in a police car came round, at this time i had it off luckily.
He asked me the same thing, he said he was off duty and wanted to hear it.. I thought that was well dodgey! I just said nah and he chipped on after about 10 minutes. Blatently someone in the carpark complained about the noise and they were coming to check it out.
No doubt in my mind, if i blared it out, they would say "right we have had reports of this blah blah" and i'd have got a ticket or something!
Yea, i was such a rebel when i was younger.. carparks for sound systems