Congressional Republicans are trying to exploit two controversies bedeviling the Obama administration to undermine the health care reform law. They are using an uproar over misguided tactics by Internal Revenue Service employees to target conservative political groups seeking tax-exempt status as an excuse to prohibit the agency from playing a pivotal role in carrying out the Affordable Care Act. And they want to use a controversy over efforts by the secretary of health and human services, Kathleen Sebelius, to encourage private donations to help enroll people in new health care exchanges as a cudgel to disrupt such efforts.

Under the health reform law, the I.R.S. is required to examine tax returns to determine who is eligible for a tax-credit subsidy to buy health insurance and who must pay a fine for failing to buy insurance. A Republican bill in the Senate would prohibit the I.R.S. from enforcing the reform law (a related Republican bill in the House would do the same unless there are certifications made that the I.R.S. will not target groups or individuals for political reasons).

An investigation by the Treasury Department’s inspector general blamed midlevel workers, confusing rules and ineffective management, but it found no evidence that the staff had been under political pressure to focus on conservative groups. Still, Republicans have scheduled hearings to try to link the scandal to health care reform. Putting any limits on the I.R.S. role in determining health subsidies for uninsured Americans would be disastrous.

The controversy surrounding Ms. Sebelius involves her efforts to persuade nonprofit groups and business executives to donate money to or otherwise assist Enroll America, a nonprofit group that aims to help people enroll in new health care exchanges, pick suitable policies and apply for tax credits. She was driven to solicit help because Republicans have repeatedly and shamefully denied requests for money needed for this purpose.