In his first congressional hearing as commissioner of the Internal Revenue Service, John Koskinen was pressed by Republican lawmakers on the rationale behind the agency’s recently proposed rulemaking on 501(c)(4) political activity.

During the February 5 House Ways and Means Oversight Subcommittee hearing, Committee Chairman Dave Camp (R-MI), who has introduced legislation to block the IRS from implementing the proposed rules, pointed to newly released emails as evidence that the Treasury Department and IRS officials were planning new rules to crack down on conservative nonprofits as early as 2012. The IRS was embroiled in a controversy last year when an inspector general’s report revealed that enforcement agents were using inappropriate criteria to flag for greater scrutiny some groups applying for 501(c)(4) tax-exempt status.

If Treasury and the IRS fabricated the rationale for a rule change, it would tend to raise questions about the integrity of the rulemaking process.

The IRS put out proposed rules last November that it said would provide clarity around the amount and the type of political activity that 501(c)(4) groups could engage in without jeopardizing their  tax-exempt status as “social welfare” groups. Camp said the IRS was focusing on 501(c)(4) groups due to “media attention,” not as a result of any confusion on how to interpret 501(c)(4) law.

“If Treasury and the IRS fabricated the rationale for a rule change, it would tend to raise questions about the integrity of the rulemaking process,” Camp said. “I want to be perfectly clear—this committee will fight any and all efforts to restrict the rights of groups to organize, speak out, and educate the public, just as unions are allowed to do so.”

Koskinen testified that he wasn’t aware of the emails from 2012, and that the IRS will carefully consider all public feedback on the proposed rules so that the standards for 501(c)(4) tax exemption are clear and can be applied consistently.

“I believe it is extremely important to make this area of regulation as clear as possible, not only because it will help guide the IRS in proper enforcement, but will also give a better roadmap to applicants and help those that already have section 501(c)(4) status understand the applicable standards and properly administer their organizations,” Koskinen said.

The IRS has already received 21,000 comments on the proposed rulemaking, and Koskinen said the expectation is that it will take some time to review all the feedback before the rules can be finalized. The deadline for comments is February 27.

ASAE is finalizing its own comments on the proposed rules, which will focus on the IRS’s expanded definition of candidate-related political activity and the suggestion that the rules might be applied to other types of tax-exempt organizations beyond 501(c)(4) groups.

Last week, Republican leaders from both the House and Senate called on the IRS to abandon the proposed rulemaking altogether. In a letter [PDF] signed by House Speaker John Boehner (R-OH), Senate Minority Leader Mitch McConnell (R-KY), House Majority Leader Eric Cantor (R-VA), and Republican leaders of the Appropriations, Finance, and Ways and Means committees, the lawmakers wrote that the proposed rules give a “strong appearance” of being politically motivated.

“It is our view that finalizing this proposed rule would make intimidation and harassment of the administration’s political opponents the official policy of the IRS and would allow the Obama administration to use your agency as a political tool,” the Republican lawmakers wrote.

IRS Commissioner John Koskinen. (Committee on Ways and Means video screenshot)