Photo by: Manuel Balce Ceneta
FILE - In this Feb. 10, 2016 file photo, Internal Revenue Service (IRS) Commissioner John Koskinen testifies on Capitol Hill in Washington. The IRS says the agency's commissioner won't appear at a House Judiciary Committee hearing Tuesday, May 24, 2106, examining whether he deserves to be impeached. (AP Photo/Manuel Balce Ceneta, File)