Leader of a special Prohibition squad (1903–1957), known as the Untouchables, which led to the downfall of Al Capone and his successor Frank Nitti, and the capture of John Dillinger. Riggs National Bank check, 8.25 x 3, filled out and signed by Ness, payable to Winifred R. Higgins for $16.57, August 21, 1945. Ness adds in the lower left corner, “Fountain Pen, Pullman Hotel.” Encapsulated in a plastic PSA/DNA authentication holder grading the autograph a “MINT 9.” In fine condition, with a small area of mounting remnants and surface loss to top edge, a central vertical fold, and expected bank stamps and cancellation holes (none affecting the crisp, clean signature).