Updated

A Senate committee's report into overprescription of powerful painkilling drugs at a Wisconsin VA hospital slammed the agency's inspector general's office for discounting key evidence, narrowing its inquiry and failing to make its report on the matter public.

The report by the Senate Homeland Security and Governmental Affairs Committee, released Tuesday and first obtained by USA Today, says the VA watchdog's investigation into the Tomah (Wis.) VA Medical Center was "perhaps the greatest failure to identify and prevent the tragedies at the Tomah VAMC."

According to the report, the Inspector General's office began investigating claims that opiates were being overpresecribed to Tomah patients with post-traumatic stress disorder (PTSD) in 2011.

The investigation, led by physician Allan Mallinger, lasted until 2014, but failed to examine whether the opiates were being prescribed in dangerous combinations with other drugs, nor whether employees felt threatened with retaliation if they raised concerns.

The watchdog's report, made public last year, failed to find that the Tomah VAMC's chief of staff, Dr. David Houlihan, and nurse practitioner Deborah Frasher, had committed any wrongdoing, though "potentially serious concerns" were raised about the high level of opiates prescribed.

Instead of making the report public, the inspector general's office briefed local VA officials and closed the case. Assistant Inspector General for Healthcare Inspections John Daigh, who made the decision to keep the report secret, told Senate investigators he could not "publish reports that repeat salacious allegations that I can’t support."

The following year, the VA opened its own investigation after Marine Corps veteran, Jason Simcakoski, died at age 35 of "mixed drug toxicity". It found that Houlihan and Frasher had failed to meet the standard of care in the vast majority of cases, and removed them from their positions at the Tomah facility.

"In just three months, the VA investigated and substantiated a majority of the allegations that the VA OIG could not substantiate after several years," the Senate committee's report stated.

"The reasons the problems were allowed to fester for so many years is because ...  for whatever reason, for years, the inspector general lacked the independence and had lost the sense of what its true mission was, which is being the transparent watchdog of VA system," said Sen. Ron Johnson, R-Wis., the committee chair.

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