When faced with institutional injustice, artists often respond by providing a critical view for society. Goya's brutal painting, "The Third of May, 1808," bore witness to the resistance of Spain to Napoleon's invading armies. Picasso's "Guernica" was his response to Germany's bombing during the Spanish Civil War. That tradition of graphic witness has evolved into contemporary form, with people all over the world appropriating those paintings and other iconic images to express outrage over the "pepper-spraying cop" incident at the University of California, Davis. Artistic responses ranged from monstrous to ridiculous, from inflammatory to humorous.

After Louise Macabitas, a psychobiology student at UC Davis, posted her photo of the "pepper-spraying cop" to Facebook it was universally recognized as an archetype. In an instant, a collective odyssey began. Others imported it into Photoshop and reinterpreted it. "Pepper-spraying cop" memes mutated into a thousand unique narratives, each expressing the indignation of a thousand protesters. Each posted a new image to social sites such as Reddit and Tumblr. Frozen in time, the casual, arrogant demeanor of one cop spraying passive students spontaneously resonated around the world.

"The power of the original image was the true engine," said James Alex, who is credited with creating five of the early altered images. "The fact that people wanted to take the Lt. Pike image, repeat him in art and democratize him, shows that art is the true enemy of repression. It was always my intention to show the absurdity of his actions."

What's a meme? Like a self-replicating gene or a virus, it's an idea or image that inspires creative participation, repeating in mutated variations. Tumblr commentator Kevin Buist noted that as a form of communication, memes are built on the idea that the audience and the author are the same. Looking, creating and sharing all blend together into one activity as a cathartic and confrontational echo chamber.

Outright copying by one artist of another's work has been legitimized since the 1970s; art movements that have incorporated appropriation include Dada, Pop and Surrealism. The concept of proprietary ownership has been challenged in copyright issues involving artists such as Andy Warhol and Jeff Koons. In the arts, the student becomes a master by copying the master. Free, open sharing inspires understanding, innovation, discourse and, as in imitation, it's called meme.

Explaining the meme phenomenon, Brady Hall, creator of the first Tumblr site, said, "Humor and irony can be powerful tools to deliver a message." He added, "Most memes are trivial, but don't underestimate satire."

By inserting the "pepper-spraying cop" into absurd situations, outrage can transform into laughter, a release of tension, a tiny bit of power in our powerless world. With this meme, the voice of ridicule magnifies, as if each has created one feather to add to the collective tar of public shame.

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Stephanie Taylor, a Sacramento artist, graduated from UCLA with a degree in history and a focus on political philosophy.

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