Information security is a top priority at Healthcare.gov, Tavenner said.
Democratic lawmakers also noted that more than 7.3 million formerly uninsured U.S. residents have signed up for health insurance through the Affordable Care Act, commonly called Obamacare.
With huge data breaches recently at Target, Home Depot and other private companies, the committee's focus on Healthcare.gov is misguided, said Representative Jackie Speier, a California Democrat. The Oversight Committee has had nearly 30 hearings on the Affordable Care Act and Thursday's was the sixth on Healthcare.gov, Democrats noted.
The Target breach potentially affects a third of the U.S. population, Speier said. "But strangely, there wasn't any interest by this committee to have a hearing on that," she said. "Let's see, 110 million people affected and no hearing. Zero people affected [by Healthcare.gov breaches], and we've had dozens of hearings. It seems like our priorities are not quite on what the American people would be interested in."
The Oversight Committee's role is to focus on government operations, Issa countered. Other committees and government agencies are looking into recent breaches in the private sector, he said.
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