Thanks!
20% is illegal in New York (nothing less that 35% in the front is allowed). I had 35% front, 20% back on my last car (which IS legal) and never had a problem. My husband's car also has the same (35%/20%) and did get approached once (while he was parked waiting for our daughter), but didn't get a ticket (he told the cop it was legal as far as he knew -- and the cop could see he was doing nothing wrong).
Ask me again in a year and I'll let you know how many tickets I got

Seriously, I see lots of cars with tinted windows that are illegal and I'm sure the cops have better things to do than pull you over for it unless they already suspect or know you're doing something wrong. The way I figure, it's the type of thing I could get an "add-on" ticket for... so if I'm pulled over for speeding or parking illegally I could also end up with a ticket for the tint. I haven't gotten a ticket since I was 21 (now 36) so I'm not too worried