What are the chances of getting caught with stolen registration sticker on license plate?

A buddy of mine couldn't afford this year's registration, so he took someone else's sticker off their plate and put it on his plate. Now I told him he's gonna get caught. I know (from personal experience) that cops have cameras or something on their car that can raise a red flag if a nearby motorist... show more A buddy of mine couldn't afford this year's registration, so he took someone else's sticker off their plate and put it on his plate. Now I told him he's gonna get caught. I know (from personal experience) that cops have cameras or something on their car that can raise a red flag if a nearby motorist has expired registration tags. My question is, could they also be alerted if he had the stolen tags? Or would they actually have to pull him over for something else and find out from DMV that it's stolen? If he's caught (or when) what will happen to him? We're in L.A. County, California.
Update: The "your friend is a retard" comments aren't helpful in any way. As stated in the question, i already think he's stupid. And why would i have to make up a "my friend..." scenario when this is all online and none of you know me anyway? No answer which contains OPINION will be given 10... show more The "your friend is a retard" comments aren't helpful in any way. As stated in the question, i already think he's stupid. And why would i have to make up a "my friend..." scenario when this is all online and none of you know me anyway? No answer which contains OPINION will be given 10 points. This is yahoo ANSWERS not opinions.
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