Sen. Bernie Sanders (I., Vt.), now a Democratic presidential candidate, was slow to take seriously reports in 2014 of the use of fake wait lists by Department of Veterans Affairs employees.

As the New York Times reported, Sanders, then chairman of the Senate Committee on Veterans Affairs, initially indicated that the controversy was being fueled by a partisan effort to undermine the government agency.

Sanders defended the VA amid reports, which first came to light in April 2014, that staffers at the Phoenix VA hospital used secret wait lists to conceal the long periods of time that veterans were delayed before receiving care. Dozens of veterans died waiting for appointments, according to whistleblowers, and the scandal eventually led to the resignation of then-VA Secretary Eric Shinseki.

"There is, right now, as we speak, a concerted effort to undermine the VA," Sanders said in May 2014. "You have folks out there now–Koch brothers and others–who want to radically change the nature of society, and either make major cuts in all of these institutions, or maybe do away with them entirely."

According to the Times, Sanders' "deep seated faith in the fundamental goodness of government blinded him, at least at first, to a dangerous breakdown in the one corner of it he was supposed to police."

"His ideological perspective blurred his ability to recognize the operational reality of what was happening at the V.A.," Paul Rieckhoff, the founder of Iraq and Afghanistan Veterans of America told the Times. "The reality was that he was one of the last people to publicly recognize the gravity of the situation."

Sanders routinely cites his experience leading the VA committee as a reason for voters to support his presidential campaign.

Sanders did eventually acknowledge problems at the agency, joining his colleagues in a bipartisan effort to pass the Veterans Access, Choice and Accountability Act of 2014, which helped boost care for veterans and established the Veterans Choice Program, which allows veterans to seek care outside of the VA in the event of significant wait times.

Despite the legislation, which President Obama signed in August 2014, significant wait times and mismanagement have persisted at VA medical facilities across the country. Just last week, an inspector general report found that veterans seeking care at a Colorado VA outpatient clinic faced excessive wait times and were denied care. In some cases, scheduling staffers used the wrong dates to make it appear that patients encountered shorter wait times.

In the face of persistent problems at the VA, veterans group Concerned Veterans for America has pushed for restructuring at the VA and allowing veterans access to more care options outside the agency’s hospitals. Sanders criticized the group for its efforts during the Democratic debate last week, accusing its leaders of trying to privatize the VA.

"Concerned Veterans of America, funded by the Koch brothers … who want to destroy Social Security, Medicare, Medicaid, every governmental program passed since the 1930s," Sanders said Thursday. "Yes, there are people out there who want to privatize VA."

Hillary Clinton, Sanders’ competitor for the nomination, has also made similar accusations against Republicans for pushing for VA reform. Clinton said last October that issues at the VA are not as "widespread" as Republicans have made them seem.

Weeks earlier, an independent assessment commissioned by the VA concluded that its flawed network of health systems demanded a system-wide reworking.