Sources: IRS official won't plead fifth at hearing on scandal

May 14, 2013: A general view of the Internal Revenue Service (IRS) Building in Washington. (Reuters)

Steven Miller, the soon-to-be-former acting commissioner of the Internal Revenue Service, has assured congressional investigators he will cooperate fully with lawmakers in upcoming Capitol Hill hearings on the IRS’ targeting of Tea Party groups, and will not exercise his constitutional right to refuse to answer questions on the grounds that doing so may incriminate him in the ongoing FBI probe, Fox News has learned.

Rather, sources say, Miller has agreed to provide his best testimony on the sudden swirl of allegations surrounding last week’s disclosure that the IRS had systematically singled out conservative-leaning groups for delays in their applications for tax-exempt status. Miller was reportedly made aware of the practice, which commenced early in 2010, as early as March 2012, but shortly thereafter assured lawmakers the IRS was not engaged in such targeting.

President Obama announced Wednesday that Treasury Secretary Jacob Lew would be accepting Miller's resignation. A House aide, though, said he is still scheduled to testify on Friday.

Congressional investigators have sought an informal deposition with Miller in advance of Friday’s hearing by the House Ways and Means Committee, but believe it unlikely Miller will grant such a session, sources said.

In addition to determining who was ultimately responsible for initiating the practice – culpability the Treasury Department’s Inspector General for Tax Administration failed to assign in his report on the subject, issued Tuesday – Capitol Hill investigators are said to be examining two other critical aspects to the scandal.

These include the dissemination of privileged tax data amassed during the targeting exercise to the left-leaning news outlet ProPublica; and allegations that conservatives listed by the targeted groups as donors were in turn singled out for adverse treatment by IRS.

The alleged improper conduct toward those donors would have been performed by a different office at IRS, sources said, than that which was responsible for the slow-walking of the conservative groups’ applications for tax-exempt status.

Both initiatives, Capitol Hill staffers told Fox News, could suggest a greater level of coordination on the overall project among – or even beyond – IRS management echelons.

Key congressional aides do not rule out the possibility that the targeting was conceived and executed by “rogue” elements in middle-management positions within IRS. But the bureaucratic culture within the agency is said to place an exceedingly high premium on compliance with orders from above – to the point of securing them, often in writing, when they are absent – and accordingly not one that would foster the emergence of so rigorous and enduring a targeting system without some measure of management supervision.

The IG report concluded that organizations with the words “Tea Party,” “Patriots” or “9/12” in their titles faced special treatment by IRS in their applications for tax-exempt status, including the agency’s application of “inappropriate criteria” to trigger reviews and other dilatory actions towards the applications.

While Miller will face more intense scrutiny, J. Russell George, the inspector general for IRS’ Tax Administration division, whose office released Tuesday’s damning intra-agency report, will also be confronted with tough questions, sources said. Capitol Hill staffers told Fox News they regard George’s report as “watered down” and are eager to ask him why his probe failed to fix ultimate responsibility for the targeting, and why he didn’t raise alarms about the practice sooner.

An IRS spokesperson did not immediately return an email seeking comment for this article.