The mural, and others like it, were painted by Missourian Thomas Hart Benton. Not only is he a significant painter of the 20th century, his family has a deep political history, both in Missouri and the U.S. as a whole. His father was a four-time elected U.S. congressman and his great-uncle, for which he was named, was one of Missouri's first two senators in the U.S. Senate. He was commissioned to paint the The Social History of the State of Missouri mural in the early 1930s. It is seen as historically and culturally significant, with Benton himself saying it might have been his best work.
Dave Marner's photographic took off on social media, with the New York Times even taking note:
Jeffrey Moore, a Columbia-based specialist in the restoration of paintings, said it’s possible the card-swapping left some sort of mark.“Chances are if you do something to the surface of a painting it leaves an impression that never goes away,” he said, adding that any damage is “probably minimal.”
After the photo took off, Valinda Freed did issue an apology: "I offer my sincere apology for my completely unplanned and thoughtless act. The Thomas Hart Benton mural, and all the magnificent artwork in the Capitol, are state and national treasures," Valinda Freed said. Thoughtless indeed.Special thanks to Michael Bersin at Show Me Progress for the tip on this story. See the full photo from Dave Marner below: