Health and Human Services Secretary Kathleen Sebelius is already claiming that seniors would be adversely affected by House-passed legislation defunding Obamacare. Nothing could be further from the truth.

Obamacare is the program inflicting harm on seniors—because, as Nancy Pelosi said, the law “took half a trillion dollars out of Medicare” to fund Obamacare. Defunding the law would make seniors much better off.

Several of the Secretary’s claims deserve specific responses. First, the Secretary alleged that, if Obamacare is defunded, the Administration “would not be able to pay [Medicare Advantage] plans,” and that “Medicare beneficiaries may be forced to dis-enroll from their current plans” as a result. But Secretary Sebelius has broad authority to prevent the kind of scenario she claims would happen—provided she wants to exercise it. Section 402(a) of the Social Security Act—42 U.S.C. 1395b-1—allows the Secretary

to develop and engage in experiments and demonstration projects…to determine whether, and if so which, changes in methods of payment or reimbursement…would have the effect of increasing the efficiency and economy of health services…through the creation of additional incentives to these ends.

In other words, Secretary Sebelius would have all the authority she needs to preserve the Medicare Advantage program, provided she wishes to use it.

The non-partisan Congressional Budget Office (CBO) agrees that HHS has broad legal authority to make changes to Medicare and other programs should Obamacare be defunded. Here’s what CBO said back in March 2011 about the impact of defunding Obamacare:

CBO and JCT assume that the Administration will interpret that [defunding] provision in conjunction with other statutes (including Public Laws 111-148 and 111-152) to give maximum effect to all laws wherever possible.

It’s important to note that, both in 2011 and 2013, CBO has not said that defunding Obamacare would cause Medicare Advantage enrollment to plummet, or the program to end. That’s because CBO assumes that HHS will use its existing authority to keep the Medicare Advantage program up and running—unless Secretary Sebelius wants to score political points by taking benefits away from seniors.

Second, Secretary Sebelius claims that Medicare “beneficiaries could have tremendous difficulty finding a doctor or experience delays in their care” if Obamacare is defunded. The truth, however, is that seniors will have difficulty finding access to care if Obamacare is NOT defunded. Non-partisan actuaries in the Secretary’s own department said that, within a decade, 15 percent of hospitals could become unprofitable due to Obamacare, and “might end their participation in the program, possibly jeopardizing access to care for beneficiaries.” If Secretary Sebelius is worried about beneficiaries’ access to care, she should support defunding Obamacare, not oppose it.

Secretary Sebelius’s letter may be intended to score political points, but it’s simply not accurate. Moreover, when it comes to seniors, the greater threat lies not in defunding Obamacare, but in allowing it to take effect.