WASHINGTON (AP) — President Barack Obama's choice to head the Internal Revenue Service goes before a Senate committee Tuesday to face tough questions about the agency's targeting of tea party groups and its ability to administer parts of the president's health law.

Obama nominated John Koskinen, a retired corporate and government official with experience managing numerous organizations in crisis, to take over the IRS in August. If confirmed by the Senate, the 74-year-old turnaround specialist would sign on to a five-year term, which would last beyond Obama's stay in office.

Koskinen came in to overhaul mortgage buyer Freddie Mac after its near-collapse in the financial crisis at the end of the George W. Bush administration. He also helped restructure the assets of the largest failed life insurance company in U.S. history, Mutual Benefit Life, and helped reorganize the Penn Central Transportation Company after it became the largest bankruptcy in U.S. history.