A Crystal Lake lawyer mocked the size of a client's penis and challenged him to a duel, according to a complaint filed by the Illinois Attorney Registration & Disciplinary Commission.

Attorney Donald Franz called client Mike Rutkowski a "small penis a------e" and "insulted Rutkowsky's manhood and choice of automobiles," the complaint said. Franz also allegedly sent an email to Rutkowski that said, "My mistake, there is only one man involved between us. I challenge you to a duel, you pick the time, place and manner."

Franz and Rutkowski were in a dispute over $400. Franz had billed that amount for his "efforts to reduce the assessed value of real property (Rutkowski) had recently purchased," the complaint said. In his answer to the complaint, Franz admitted to the "general characterization" of the small-penis quip but "denies insulting Rutkowski's manhood or choice of automobiles." He also said the duel challenge was taken out of context.