Metro’s Inspector General investigated a whistleblower complaint three years ago alleging that workers had  falsified inspection reports involving bridges, platforms and tunnels. The watchdog also notified Metro’s management of the allegations, a spokeswoman for the mass-transit agency said this week.

But what happened with those findings — or whether the August 2013 whistleblower complaint to the Office of Inspector General (OIG) triggered a broader review of the subway’s inspection practices — isn’t clear. Metro declined to release the report Thursday.

The inspector general’s disclosure comes after Metro announced last week that six workers had been fired and others had been disciplined for doctoring track inspection reports. Metro said an investigation into the July 29 derailment near East Falls Church found the practice involved nearly half of the agency’s 60-person track-inspection department and had been going on for three years. It also contributed to the conditions that caused the Silver Line train’s derailment, the agency said.

Union officials, who challenged management’s account and vowed to defend the disciplined employees, said Metro suffered from a workplace culture in which employees feel coerced into going along with sloppy or unsafe practices, and that those who speak out often face retaliation. Jackie Jeter — who is president of the Amalgamated Transit Union Local 689, Metro’s largest union — also  said whistleblower complaints often go nowhere.

In response, Metro General Manager Paul J. Wiedefeld said the agency has several policies in place to encourage whistleblowers to come forward without fear, and that many do.

Which is it? Like so many things at Metro, the inspector general’s disclosure creates more questions than answers.

Helen Lew, who became Metro’s first inspector general in May 2007, said through an agency spokeswoman late Wednesday that no one had come forward to her office with any whistleblower allegations of falsified track inspections in the past three years.

But Lew said her office looked into a complaint in August 2013 alleging that bridge, platform and tunnel inspections had been falsified. She did not specify the time frame the allegations covered.

Following its investigation, the inspector general’s office sent a report of its findings to former Metro assistant manager Rob Troup in September 2015. In response, Metro management developed a “corrective action plan,” the spokeswoman said.

We asked for an interview with the inspector general, but a Metro spokeswoman said Lew was away from the office. Through the spokeswoman, Lew also said the OIG does not “publicize the results” of its investigations. Lew did note, however, that her office had just launched an audit of Metro’s Structures Inspection Program — which seems more than a tad overdue.

The inspector general was set up, at least in part, to foster a better safety culture at Metro and investigate and shield whistleblowers. As Metro has spiraled downward in reliability and safety in recent years, it’s not clear what the watchdog has been watching.

We’ll update you when we learn more.

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