With the exception of an independently owned low-speed tourist train (the Orford Express) on one small segment between Magog and Sherbrooke, there was no passenger service on the MMA system.

Accountants from the la Caisse de dépôt et placement du Québec wrote that company's investment in MMA down to a nominal $1000 from 2008 onward.

[15] Largely due to the lack of money for track maintenance and equipment, adverse winter weather conditions, and possibly the practice of running with single person crews, from 2003 to 2013 MMA recorded an accident rate of 36.1 accidents per million miles travelled, versus a national average of 14.6/million miles traveled for all of North America, according to data from the Federal Railroad Administration.

[16] Freight volumes continued to drop as manufacturers, needing to meet customer demands for smaller quantity just in time delivery in order to reduce inventories, began to prefer trucking firms as faster and more reliable than MMA.

[17] A 2008 proposal to return passenger train service to the Eastern Townships on the 150 kilometres (93 mi) route between Montréal and Sherbrooke was studied but never implemented.

The MMA-owned section of the line from St-Jean-sur-Richelieu to Sherbrooke would have required costly upgrades to tracks and bridges in order handle Via Rail passenger trains operating at 110 kilometres per hour (68 mph).

[18] In 2011, the Twin Rivers Paper Company of Madawaska, Maine, the largest customer on the former BAR line, intervened in a United States District Court lawsuit which sought to allow the company to deal directly with Canadian National Railway (reporting mark CN) after years of problems with what it described as "MMA's exorbitant pricing structure, ineffective service, and annoying executives."

[20] Upon failing to break free from MMA's local monopoly through legal action,[21] Twin Rivers Paper Co. resorted to transshipment of its entire output across the Canada–United States border to Edmundston, New Brunswick by truck for placement directly on CN trains.

[23] The STB subsequently postponed action on the request in late April, after the railroad and Maine officials agreed to negotiate to prevent the lines from being abandoned, which the state said could negatively affect the economy of the area.

Transporting oil allowed it to re-hire laid-off workers and purchase additional locomotives (rebuilt General Electric C39-8s originally constructed in 1986).

[37] By early 2013, environmental groups and Maine state officials were expressing concern about the increasing amounts of crude oil on both the MMA and its rival Pan Am Railways in the wake of a string of minor derailments on both railroads.

"[38] In a March 2013 Associated Press interview, MMA chief executive Robert Grindrod dismissed these concerns, stating "The statistics tell you how much has been transported, but to the best of my knowledge, there hasn't been any spilled or released,".

The train had been left unattended and improperly secured overnight on the mainline, with one locomotive running, on a -0.92% grade leading 18 kilometres (11 mi) from Nantes, Quebec downhill to a 10 miles per hour (16 km/h) curve where the line entered downtown Lac-Mégantic.

"[48] Questions were also raised about the condition of the line; on July 11 a Magog newspaper reported one in ten railroad ties to be rotten with many spikes loose enough to be removed by hand.

In Quebec, MMA had continued operation from Farnham with a skeleton staff after the derailment, having laid off 24 Canadian employees[51] and 64 workers in Maine in July 2013 as the line remained blocked by wreckage at Lac-Mégantic.

[57] Following the tragedy, parent company Rail World faced hundreds of millions of dollars in lawsuits and environmental cleanup costs due to the destruction of downtown Lac-Mégantic.

[58] It is unclear how much of the disaster's cost was paid by liability insurance; laid-off MMA workers reported problems obtaining the severance pay owed them[59] and cheques to suppliers were rejected due to non-sufficient funds.

[62][63] According to Burkhardt, the financial obligations of both US and Canadian subsidiaries "now exceed the value of their assets, including prospective insurance recoveries, as a direct result of the tragic derailment at Lac-Megantic.

[74] On September 12, Transport Canada shut down part of the MMA line[75] after an inspection of six track segments found substandard rail conditions which included a concentration of defective ties on a section near a propane storage facility.

[77] Orford Express, a special tourist train which used MM&A lines between Magog and Sherbrooke, carried $50–100 million in liability insurance independently of MMA and planned to continue its regular service.

The terms of the sale were announced in mid-February 2014 when the new railroad named Central Maine and Quebec Railway (reporting mark CMQ) was registered in the United States and Canada.

[82] On January 30, trustees filed a US lawsuit on behalf of the bankrupt railway, alleging that World Fuel Services was negligent in failing to properly label the train's dangerous cargo and that, had its true volatility and inflammability been honestly disclosed on shipping documents, MMA procedures would have prevented it being left unattended on a main rail line.

[83] On May 12, 2014 the Montreal, Maine and Atlantic Railway was charged with 47 counts of criminal negligence; engineer Thomas Harding, manager of train operations Jean DeMaître and rail traffic controller Richard Labrie were arrested and will appear in Lac-Mégantic's court.