House Committee on Oversight and Government Reform Chairman Darrell Issa demanded all documents and communications between the IRS and President Barack Obama's White House after the healthcare overhaul law was signed into law in March 2010, in a letter released on Wednesday. Issa has challenged the Obama administration's authority to administer the healthcare law in states that are refusing to cooperate. The IRS is charged with distributing health insurance tax credits through the state exchanges. Issa argues that federally-created exchanges, set up in the resisting states, cannot deliver the tax credits.