The former Republican congressman and auctioneer also had a brief career selling tax credits, including one that the I.R.S. said did not exist and another it said was rife with fraud.

The Senate confirmed former GOP Rep. Billy Long to lead the IRS, where he would be responsible for implementing the major new tax legislation Republicans are hoping to enact and overseeing cuts to budgets and the workforce initiated by the Department of Government Efficiency.

The Senate confirmed former Rep. Billy Long (R-Mo.) to serve as IRS commissioner, becoming the sixth leader to hold the job this year.