Bringing the IRS to heel can start with re-energizing and expanding congressional investigations and holding accountable those responsible for the targeting and other abuses.

The day after Republicans won solid majorities in the House and Senate, House Speaker John Boehner and Senate Majority Leader-to-be Mitch McConnell outlined priorities for the newly elected Congress. High on the list is fundamental tax reform. In addition to overhauling the federal tax code, however, Congress should rein in the Internal Revenue Service.

Bringing the IRS to heel can start with re-energizing and expanding congressional investigations and holding accountable those responsible for the targeting and other abuses.

Much has already been learned about the arrogance of the IRS from the House investigations of the agency's targeting of conservatives. The revelations emerged despite strenuous efforts by Democrats in Washington and by the IRS itself to block inquiries and deny the existence of political targeting - targeting that the former head of the IRS Exempt Organizations Unit, Lois Lerner, eventually acknowledged and apologized for in May 2013.