I do web work and some graphics for a guy that does silkscreening if you need someone to do it. Personally I like the following design:
I Like the
POLICE
On a bright Yellow shirt they would think you were the real thing until they had already gave you safe passing distance and speed and then it would be too late to be rude! Hahahhahahahhaha
Oh! and the front would read-
!REKCUS
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Sunrise saturday,
I was biking the backroads,
lost in the moment.