The limits created by section 6103 became clear during the hearings this month. On May 17, Representative Aaron Schock of Illinois asked Steven Miller, then the acting IRS commissioner, to comment on questions received by anti-abortion groups. One was about whether the group educates on both sides of an issue and another was on the content of its prayers.

‘Pains Me’

“It pains me to say I can’t speak to that one either,” Miller said, though he said that as a general rule, he would be surprised by that type of question to a group.

Specific examples shape public perception, giving taxpayers an edge when engaging the IRS in a congressional hearing, said Joshua Blank, a tax law professor at New York University who supports current privacy rules.

“The IRS is not able to counter those arguments with similarly persuasive specific examples,” he said. The focus on IRS misdeeds is an unusual departure from the agency’s typical ability to shape its image by emphasizing prosecutions of tax cheats, he said.

Congress created Section 6103 in 1976, following revelations that President Richard Nixon had sought IRS audits of his political opponents.

While the tax system had some privacy protections, Section 6103 created a clearer set of rules in place of executive branch discretion. They included an assumption that taxpayers’ information is private without a specific exception.

Prison, Fines

Unauthorized disclosure of such information is a felony with penalties of up to five years in prison and a $250,000 fine. IRS employees also can be disciplined for violations.

Taxpayer privacy is ingrained in agency employees, and includes restrictions on using internal access to look up such things as the tax records of celebrities or their own daughters’ boyfriends, said Mark Matthews, a former IRS deputy commissioner and criminal investigation chief.