Every state is different, what I was told for California is that as long as it shines amber the clear lense is legal... I have seen some bulbs that are silver so that you can't see the amber bulbs inside, but when they are lit they shine amber... I have the clear lenses with the amber bulbs...
Legallity depends on your locality and or how well it is enforced. For what it's worth, I'm in NJ also. Up till last year, I had regular (frosted) corners without a problem. Last year I replaced them with diamond clear with chrome bulbs. The D went through a state inspection station with them without them saying anything. The truck passed inspection. You can see pictures in my gallery. I know a lot of other D owners in NJ who have them (clear and diamond), and have not had problems. The diamond clears do not have any reflectors at all so there is no way they are legal anywhere.
There is a maker of the clear corners (not diamond cut though) that has a small yellow reflector on it. Kind of ruins the look imho though. As far as legality... Put it this way, if a cop pulls you over because he/she didn't notice a reflector, then he/she's got way too much time on their hands and they're going to find something to pull you over for regardless.
I've had clear corners with clear bulbs for a year now and no problems.
Thanks for all the advise everyone...I asked too soon.....A guy at work has them on his Dakota and got pulled over on his way to work. Good thing hes related to cops!
No tickets but warnings to remove them. He has alteeza clear corners in fornt and he has to remove his covers from the tail lights. All I can say is..THAT SUCK!