(CBS NEWS)-- Amid ongoing scrutiny over alleged IRS discrimination targeting practices, acting IRS commissioner Steven Miller on Friday apologized on behalf the agency for "the mistakes that we made and the poor service we provided," but he said he did not think partisanship drove the practices now under investigation. Miller also insisted he did not "mislead" either the American people or Congress.
Public questioning began Friday morning in the House Ways and Means Committee, where Miller and J. Russell George, the Treasury Inspector General for Tax Administration (TIGTA), were faced with questions about the targeting by the IRS of conservative groups seeking tax-exempt status. Earlier this week, TIGTA released a report detailing the implementation of these practices by IRS officials.
"First and foremost, as acting commissioner, I want to apologize" on behalf of the IRS, Miller said. "Partisanship or even the perception of partisanship has no place at the IRS."
But, he said, "I do not believe that partisanship motivated the people who engaged in the practices described."
"I think that what happened here is that foolish mistakes were made" in the name of sorting through an increase in applications, Miller said. The IRS "learned its lesson," he added, and has "implemented changes to make sure that this type of thing never happens again."
According to George, the IRS was guilty of targeting conservative groups, delaying tax-exempt applications for those groups, and requested unnecessary information when scrutinizing those applications.
"The IRS was following inappropriate criteria," George said. "These findings have raised troubling questions about whether the IRS has effective management, oversight and control" over certain parts of the agency.
On Wednesday, President Obama announced that Miller is stepping down from his post. The president called the conduct at the IRS "inexcusable." A day earlier, George released a report blaming lax leadership for the fact that IRS agents put undue scrutiny on conservative groups applying for tax-exempt status.
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