As part of their investigation, Ways and Means Committee staff have interviewed 25 IRS officials and are reviewing about 300,000 internal IRS documents, Boustany said.
Also Wednesday, the Republican staff of the House Oversight and Government Reform Committee issued a 19-page update of its investigation. Much of the memo detailed how Democratic politicians, including Obama, were publicly vilifying conservative political groups at the same time that IRS agents were targeting them.
The memo included excerpts of interviews with IRS workers who said they were aware of the publicity surrounding some of the groups.
Rep. Elijah Cummings of Maryland, the top Democrat on the Oversight committee, dismissed the memo.
"Unable to prove a link between the White House and the IRS conduct, Republicans now allege that President Obama and other Democrats sent subliminal messages through the media directing the IRS to target tea party organizations," Cummings said in a statement. "This latest partisan staff memo demonstrates that Republicans are grasping at straws. It's time for the committee to stop the political games and start working to restore the public's confidence in the IRS."
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