The Greek letters might give you a clue, indicating that a fraternity or sorority might be responsible. Here's another clue.
Bishop John Carroll was the first American bishop and the founder of Georgetown University. He was a member of the prominent Carroll family -- his brother Daniel owned most of the land where the Capitol is now located and his brother, "Charles Carroll of Carollton", signed the Declaration of Independence.
The painted lion in the first photo is called the Pacelli Lion and is the target of painting by fraternities and sororities at JCU.