J. Russell George

J. Scott Applewhite

WASHINGTON - The Treasury Department investigator whose probe of the Internal Revenue Service's treatment of tea party groups helped fuel a national uproar failed to tell Congress that his own investigators found no evidence the targeting of conservatives was politically motivated, a top House Democrat said Friday.

Rep. Elijah Cummings, D-Md., released documents that also seemed to indicate progressive groups seeking tax-exempt status may have been handled the same way as conservative organizations. While it has been known the term "progressive" appeared on a list that IRS screeners used, it is unclear whether liberal organizations received the same close scrutiny as conservative groups.

The documents were attached to a letter Cummings sent Friday to Rep. Darrell Issa, R-Calif., who chairs the House Oversight and Government Reform Committee.

That panel, on which Cummings is the top Democrat, has been among three congressional committees investigating the IRS' handling of conservatives' applications for the tax-exempt designation.

Cummings' letter is the latest Democratic attempt to challenge the fairness and accuracy of the Treasury investigator's probe of the IRS.

Several Republicans have said they believe the IRS' tough handling of conservative groups was politically motivated and flowed from the White House or allies of President Obama. There has been no evidence of any political motivation or of involvement by any top officials outside of the IRS.

Ali Ahmad, a spokesman for Issa, said the documents Cummings released don't disprove that conservative groups received harsher treatment than others.

Documents attached to Cummings' letter included an email that a top investigator for Treasury Inspector General J. Russell George sent on May 3, 2013, to other officials in George's office. George conducted the IRS probe and released a report two weeks later.

The email said that after meeting with George, his investigators examined 5,500 emails from IRS screeners. Those emails showed that the workers set aside applications from tea party and other groups "because the IRS employees were not sure how to process them, not because they wanted to stall or hinder the application.