Via Wired:

Forty-six artists, including Shepard Fairey, have contributed black-and-white artwork to the Police Brutality Coloring Book, a 48-page DIY publication inspired by incidents of violent police action against Occupy Wall Street activists.
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The idea to create a coloring book arose during a conversation between Nelson and Anton Newcombe, leader of the band Brian Jonestown Massacre. Afterward, Nelson contacted artists he knew as well as some he met or heard about in Zuccotti Park, ground zero for the Occupy Wall Street movement. He also asked Noah Becker, friend and editor of arts website Whitehot Magazine, to participate. “I did a drawing in about 15 minutes during our meeting,” Becker told Wired.com, “and in the midst of me drawing, Shepard Fairey called to say he was really excited about the idea. Then things just took off.”
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The result is a photocopied, saddle-stitched book, with artwork ranging from crude sketches to fine illustrative art — most of which is conducive to coloring, some of which isn’t. Nelson describes it as “basically a punk-rock ‘zine, like what I used to do in the ’80s.”

You can view all the pages of the coloring book here, but it's possibly not quite suitable for work due to subject matter.