It's an excerpt from Subway Lives by Jim Dwyer.
"For all these kids, seeing their name on the news was just another way of getting up-writing their tags, their graffiti names. So was getting arrested. One week, ***** Smith was busted. In a rare twin success, the cops nabbed JA the following weekend. He was taken to the transit police vandal squad office in the East New York section of Brooklyn, where he was booked. "I went into the bathroom to wash the fingerprint paint off my hands," JA recalled, "and I looked in the mirror and saw something on the wall behind me. Nah. Couldn't be. I turned around, and sure enough, there was SMITH, in that squiggled hand- writing, above the urinal. He'd tagged the vandal squad's own bath- room. In their own fingerprint paint.""