The former head of the IRS said Tuesday that he was aware of some aspects of his agency's targeting of conservative groups in the spring of 2012, and took what he called the correct action of ensuring the situation would be independently reviewed.
However, Douglas Shulman denied full awareness of what was happening at the time, saying subordinates failed to inform him of the details.
"I agree that this was an issue that when someone spotted it, they should have run it up the chain," said Shulman, whose tenure as IRS commissioner coincided with the controversial targeting. "Why they didn't, I don't know."
Shulman was one of three witnesses who appeared under oath before the Senate Finance Committee at the second congressional hearing on the practice condemned by President Barack Obama and leaders of both parties.
In other new details disclosed at Tuesday's hearing, Shulman's successor as acting IRS commissioner admitted he helped engineer a clumsy public disclosure of the controversy through a planted question at an American Bar Association event on May 10.
The question prompted IRS official Lois Lerner to apologize at the event for the targeting, which was to be made public in coming days by the release of a report by the Treasury's inspector general on tax issues.
Steven Miller, who has been ousted as acting commissioner in response to the targeting issue, called the planted question a "bad idea" intended to create an initial IRS apology by Lerner before the story broke with the release of the inspector general's report.
Lerner, who heads the division involved in the political targeting, is scheduled to appear Wednesday before the House Oversight Committee in the third congressional hearing so far on the matter.
A spokesman for the committee said Lerner's lawyer informed the panel she would invoke her constitutional right against self-incrimination and refuse to answer questions.
Republicans contend the controversy is part of a pattern of a White House gone wild, while Democrats insist that what happened -- while unacceptable -- was initiated within the IRS instead of being a practice called for or supported by Obama.
In his first public comments since the matter came to light this month, Shulman said he properly notified the appropriate Treasury inspector general about the problem when he learned that IRS workers were categorizing groups seeking tax-exempt status according to criteria including whether they had "tea party" in their name.
His statement drew angry responses from members of the Senate panel.
Committee Chairman Max Baucus, D-Montana, asked why stronger action wasn't taken to halt the problem when IRS officials first became aware of it in June 2011.
Shulman replied he didn't know anything about it at that time.
"If you don't know, it sounds like somebody wasn't doing his job," Baucus shot back, calling the agency's response and the continued improper practices "outrageous."
Baucus also asked Shulman what it was about the IRS culture that allowed the situation to happen in the first place.
Senate panel in IRS grilling
Shulman responded that he left his post six months ago, adding: "I don't think I can answer that question."
"You certainly have more thoughts than that," Baucus said.
When questioned by GOP Sen. Orrin Hatch of Utah, Shulman said he was unaware of the "full set of facts" about what happened in his agency until the inspector general's report was made public on May 14.
However, he said that "some time in the spring of 2012," he was made aware that a list was being used to determine the scrutiny of groups seeking tax-exempt status and that the name "tea party" was one of the criterion.
"I didn't know the scope and the severity of this," Shulman said, adding that he took "at the time what I thought was the proper step" by making sure the inspector general looked into the matter.
Under tough questioning by another Republican, Sen. John Cornyn of Texas, Shulman said he regretted what happened on his watch but refused to take personal responsibility for it.
"I certainly am not personally responsible for creating a list that had improper criteria on it," he added.
Other Republicans took objection with Miller, who said the targeting was wrong and a mistake but denied it amounted to deliberate political targeting.