The official who disclosed that the Internal Revenue Service had used inappropriate criteria to examine groups seeking tax-
exempt status insisted Wednesday that she did nothing wrong but also declined to answer questions from lawmakers, saying she did not want to incriminate herself in any future criminal proceedings.

Lois G. Lerner, who led the IRS tax-exempt unit at the center of the scandal, invoked her Fifth Amendment right against self-
incrimination during an appearance before the House Oversight and Government Reform Committee, saying that members of the panel had already falsely accused her of providing false information to Congress.

“I have not done anything wrong,” she said. “I have not broken any laws. I have not violated any IRS rules or regulations. And I have not provided false information to this or any other congressional committee.”

On the advice of counsel, she said, she would not answer further questions.

Before dismissing her, the committee’s chairman, Rep. Darrell Issa (R-Calif.), asked Lerner to review a transcript of an interview she gave to the Treasury Department watchdog as part of an investigation into the matter. Lerner confirmed the contents of the document but declined to answer further questions.

Issa then dismissed Lerner and her attorney against the objections of Rep. Trey Gowdy (R-S.C.), who said that Lerner had waived her right to invoke the Fifth Amendment by making an opening statement.

“She ought to stand here and answer our questions,” he added later as people in the audience applauded.

When the hearing concluded six hours later, Issa announced that he might recall Lerner before the committee and review whether she waived her Fifth Amendment rights by giving an opening statement and answering questions about the document.

Accordingly, Issa said the hearing “stands in recess, not adjourned.”

Lerner’s attorney had informed the committee on Tuesday that she would invoke the Fifth Amendment, but committee aides said she was required to appear anyway.

Lerner was the official who revealed during a May 10 American Bar Association conference in Washington that employees in the IRS’s tax-exempt unit in Cincinnati had improperly scrutinized applications from dozens of organizations. The revelation, which came before the agency revealed the information to lawmakers or the news media, provoked bipartisan outrage and has fueled national debate about the role and reach of the federal government.

In her opening statement, Lerner noted that she has been a federal employee for 34 years, holding positions at the Justice Department, the Federal Elections Commission and the IRS. She said she became director of the IRS’s tax-exempt unit in 2006, making her responsible for a budget of almost $100 million and 900 ­employees, who process more than 60,000 applications for tax-exempt status annually.

“I am very proud of the work that I have done in government,” Lerner said.

Some Republicans said that Lerner’s opening statement could be interpreted as a “subject-matter waiver,” meaning she had made factual statements about the case that then opened the door for the committee to ask her for further details. But to hold her in contempt, the committee would need a federal judge to rule in favor of the move.

Lerner’s lawyer, William W. Taylor, adamantly disagreed with suggestions that his client had opened herself up to contempt charges.

“The law is clear that a witness does not waive her Fifth Amendment rights not to testify as to facts by asserting that she is innocent of the wrongdoing with which she is accused,” Taylor wrote in an e-mail.

Stanley M. Brand, who has represented several clients who faced congressional scrutiny, agreed that Lerner did not provide “a waiver” for lawmakers to ask her questions.

“The question would be whether she made statements about the factual substance of the subject, but courts will be loath to divest someone of their rights absent a clear and unequivocal waiver,” Brand wrote in an e-mail.

Once Lerner left the committee room, lawmakers turned their attention primarily to Douglas Shulman, the Bush administration appointee who led the IRS during President Obama’s first term. He was joined at the witness table by J. Russell George, the Treasury inspector general for tax administration, and Treasury Deputy Secretary Neal Wolin.

Rep. Elijah E. Cummings (Md.), the ranking Democrat on the House panel, criticized Shulman for not correcting his March 2012 testimony after learning that IRS employees had indeed targeted conservative groups.

“It seems to me that you would come back even if it were a phone call or a letter,” Cummings said. “I mean, common sense.”

At various points Issa charged that George, who has been largely spared the grillings reserved for other officials in previous hearings, failed to keep Congress informed about his findings as his audit began last year.

Issa told George that “we do not wait 10 months to find out that there’s a there there” and called the delay “the greatest failing of an otherwise well-regarded inspector general.”

But George reminded the committee that his office conducted an audit, not a formal investigation. He added that there are “established procedures for conducting an audit” to ensure fairness and noted that information given to Capitol Hill “sometimes is not retained on the Hill.”

Under questioning by Rep. Jim Jordan (R-Ohio), who chairs an oversight subcommittee that first probed allegations of IRS wrongdoing, Shulman said he did not discuss the IRS targeting of conservative groups with the White House during visits to the White House that Jordan said numbered more than 100 between 2010 and 2011.

“It would not have been appropriate to have a conversation with anyone at the White House about the subject of discriminating against conservative groups,” Shulman said.

Shulman later clarified that he had visited the White House complex — which includes the adjoining Eisenhower Executive Office Building and the New Executive Office Building located across the street — for “The Easter Egg Roll with my kids” and for various meetings regarding the IRS budget, the enforcement of tax laws, efforts to improve the federal finance aid process and meetings on the implementation of the 2010 health-care reform law.

At various points Issa charged that George, who has been largely spared the grillings reserved for other officials in previous hearings, failed to keep Congress informed about his findings as his audit began last year.

Issa told George that “we not wait 10 months to find out that there’s a there there” and called the delay “the greatest failing of an otherwise well-regarded inspector general.”

But George reminded the committee that his office conducted an audit, not a formal investigation. He added that there are “established procedures for conducting an audit” to ensure fairness and noted that information given to Capitol Hill “sometimes is not retained on the Hill.”

Aaron Blake, Zachary A. Goldfarb, Juliet Eilperin contributed to this report.

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