Transport Minister Garneau dismissed the Lac-Mégantic rail safety citizens' coalition, as conspiracy theorists for demanding an independent Commission of Inquiry into the 2013 oil train disaster.On Parliament Hill—supported by Bloc Québecois, NDP, and Green Party MPs— coalition representatives unveiled a 3600-person petition endorsing their demand.Garneau insisted that the 2014 Transportation Safety Board investigation report has fully determined causes of the disaster. He is mistaken. It left many unanswered questions about what happened, why it happened, and who was responsible.Here are a few:Transport Canada granted permission to Montréal Maine and Atlantic—a delinquent railway company with an appalling safety record—to operate its massive oil trains with a single crewmember, and with virtually no compensatory safety precautions. It was a highly controversial decision within Transport Canada itself, and was opposed by the company union.Why and how was permission granted?  What were the inner workings that led to this decision? Who made it and who was in the loop, up the departmental accountability ladder including to the Minister's office? That wall of silence has never been breached.Why did Transport Canada ignore the findings of a National Research Council report, which recommended not going ahead with single person crew trains until a number of measures were taken to compensate for the commensurate reduction in safety, including the need for a two-year pilot project prior to proceeding.What was the specific nature the pressure exerted by the railway lobby on behalf of the company, which succeeded in overriding the opposition.More generally, what is the relationship between a powerful industry, which in effect regulates itself, and an under resourced, deferential Transport Canada that resulted in multiple regulatory failures in the lead-up to Lac Mégantic.The original TSB investigation team report identified six causes of the tragedy related to Transport Canada's allowing MMA to operate with single person crews. These causes were all erased in the final report. Why?Why did the TSB itself not hold a public inquiry into this unprecedented tragedy, as provided for in its legislation?All subsequent civil and criminal proceedings were settled behind closed doors with the exception of the criminal negligence trial against three front-line workers. And in that trial, no government, industry or company decision-maker was called to testify.An inquiry can fill this critical void. Although it cannot bring criminal or civil indictments, it can compel witnesses to testify under oath and be cross-examined; it can [unlike the transportation Safety Board] make a determination of misconduct and assign blame against individuals or organizations.Another essential purpose: an inquiry can make recommendations for reform to improve the rail safety regime at a time when unprecedented volumes of oil are being transported by rail; for example, measures:

• To strengthen the independence and countervailing power of safety regulatory bodies;
• To provide additional resources and enforcement tools to strengthen oversight capacity, and fulfil its primordial obligation to protect the public.

Other disasters— for example, the Hinton Alberta rail crash; the Ocean Ranger oil rig sinking; the Walkerton e. coli water contamination; the Dryden Ontario air crash— have warranted inquiries.   The death and destruction wrought at Lac-Mégantic was unprecedented in modern Canadian history. It killed 47 persons, orphaned 27 children, incinerated the town centre, and spilled six million litres of toxic Bakken shale oil into the environment.If there was ever a case for such an inquiry this is it.Former Transportation Safety Board chair, Wendy Tadros asked, at the release of the TSB report: “Who was the guardian of public safety? That's the role of government . . . And yet this booming industry — where unit trains were shipping more and more oil across Canada, and across the border — ran largely unchecked."Why indeed!  Her question is still largely unanswered almost six years after the tragedy.Bruce Campbell is the author of: The Lac-Mégantic Rail Disaster: Public Betrayal, Justice Denied, [James Lorimer]. He is currently adjunct professor, York University, Faculty of Environmental Studies.