WASHINGTON — In response to an announcement that the head of the Internal Revenue Service’s tax-exempt organizations division will invoke the 5th Amendment and refuse to testify at Wednesday’s hearing before the House Oversight Committee, a spokesman for the committee noted that, whether or not she plans to speak, she is still required to attend.

An attorney for Exempt Organizations Director Lois G. Lerner informed the committee by letter Monday that Lerner would claim her constitutional right against self-incrimination, thus depriving the committee of potentially valuable testimony in the rapidly widening scandal over the tax collector’s targeting of conservative and tea party groups for extra audits and delays of their requests for tax exemption.

“Ms. Lerner remains under subpoena from Chairman [Darrell] Issa to appear at tomorrow’s hearing,” Committee communications advisor Ali Ahmad told The Daily Caller via email, adding that “the Committee has a Constitutional obligation to conduct oversight.”

Although remaining silent spares Lerner from providing sworn testimony that could be used against her in the criminal investigation opened last week by Attorney General Eric Holder, the appearance is still likely to be a harrowing experience. Legislators frequently vent outrage and anger at silent witnesses.

The Los Angeles Times first reported the news that Lerner plans to take the 5th, based on the Department of Justice’s probe.

In the letter to the committee, Lerner’s lawyer William W. Taylor III conveyed her intention to avoid testifying Oversight, requesting that she be excused from attending the hearing, which would “have no purpose other than to embarrass or burden her.”

The Oversight Committee does not appear inclined to honor that request.

“Chairman Issa remains hopeful that she will ultimately decide to testify tomorrow about her knowledge of outrageous IRS targeting of Americans for their political beliefs,” he added.

A representative for Ohio Republican Rep. Jim Jordan declined to comment beyond the committee’s statement, but during testimony by Holder last week, Jordan, an Oversight Committee member, raised the prospect that the Justice Department investigation would cause Lerner to clam up.

“We don’t want [Lerner] to come here and say, ‘I can’t say anything about that because Mr. Attorney General has a criminal investigation going on,'” Jordan said during Holder’s appearance before the House Judiciary Committee.

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