For the record, in New York State you may not cover your license plate with anything - not even a clear glass or plastic frame, let alone anything tinted.
I know that some officers - especially town and village cops - enjoy getting towards their ticket quotas by writing drivers up for these. I don't have a cover, so I've never had the pleasure of being on the receiving end of a ticket for this.
You can find this in Subdivision 1 of Section 402 of the Vehicle and Traffic Law.
The state legislature has some bills in to change this section of law. Not sure they are going to go anywhere this year, though.
