John Koskinen, commissioner of the Internal Revenue Service (IRS), waits to speak during a National Press Club luncheon in Washington, D.C., U.S., on Tuesday, March 31, 2015. Koskinen, 75, became commissioner in December 2013. He is trying to persuade Congress to increase the agency's budget after a 3 percent cut this year. At the same time the agency's workload has expanded, partly because of its responsibility to implement parts of Obamacare. Photographer: Andrew Harrer/Bloomberg via Getty Images