is it graffiti, if...

Paul "Moose" Curtis creates his art by erasing dirt from public surfaces.

British authorities aren’t sure what to make of the artist who is creating graffiti by cleaning the grime of urban life. The Leeds City Council has been considering what to do with Moose. "I’m waiting for the kind of Monty Python court case where exhibit A is a pot of cleaning fluid and exhibit B is a pair of my old socks," he jokes.

So is it graffiti, or isn't it?
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