Thomas Walsh, who represents train driver Tom Harding, says he is concerned that someone permitted the lead engine, likely a key piece of evidence, to roll out of the jurisdiction of Canadian authorities when court proceedings have barely begun.
Walsh added that he wonders how many hands — and whose hands — locomotive MMA 5017 passed through on its way to its parking spot at a Maine rail yard.
"If the state of the train became central (to the Crown's theory), and if there was some kind of a strong risk of contamination, then it would become a major issue in an eventual trial," Walsh said in an interview.
"The defence as well as the Crown have an obvious interest in making sure that there's a proper chain of possession, and if there isn't then the exhibit could become, for all intents and purposes, worthless."
Many trials have "foundered" over issues involving the chain of possession of evidence, he noted.
Walsh made the remarks after The Canadian Press informed him the engine was stored at a facility owned, until recently, by the now-bankrupt Montreal, Maine and Atlantic Railway, the same company implicated in last summer's deadly catastrophe.
The Canadian Press also learned that the damaged locomotive, which played a critical role in the events that led to the derailment, was transported to the Derby Rail Yard by MMA employees.
The railway itself and three of its employees, including Harding, were each charged with 47 counts of criminal negligence causing death, one for each victim of the crash that wiped out part of the Quebec town. If convicted, the men could face life sentences.
"It's like handing the gun back to the murder suspect," Walsh said.
"It's very unusual."
A recent report by The Canadian Press revealed that MMA 5017 is stored at the facility in Milo, Maine, where it had been slated to go to auction Aug 5 along with another two dozen engines that belonged to the railway.
After the report was published, Quebec provincial police made a sudden plea to an MMA creditor to hold back from selling the locomotive until court proceedings have been completed. The creditor, the Bangor Savings Bank, says it agreed to the request and pulled it from the auction.
The bank has said counsel for the U.S.-based bankruptcy trustee overseeing the MMA file gave it the the green light to sell the locomotive.
The trustee, Robert Keach, has not responded to interview requests.
Meanwhile, it remains unclear why the locomotive was moved to central Maine.
A spokeswoman for Canada's Transportation Safety Board said nobody was available to comment on the decision to ship the locomotive to the U.S.
The agency's Jacqueline Roy also said no one was available to answer questions on how the TSB has ensured nothing was compromised on the locomotive during its time in Maine, nor to explain how it nearly ended up on an auction block.
In an email, Roy said MMA employees brought the locomotive to the Maine yard, where the unit is being held on the TSB's behalf.
She said the machine won't be released until after the agency has issued its final report on the Lac-Megantic investigation, which is expected soon.
Roy said TSB investigators examined the unit in Canada last year between July and December. The TSB, she added, took control of the locomotive from Quebec provincial police.
A spokeswoman for the police force said she couldn't immediately provide information on how the locomotive ended up in the U.S.
"The investigation concerning the Lac-Megantic tragedy is our responsibility," said Aurelie Guindon.
"On the other hand, there were many stakeholders involved. Among others, the TSB did part of the investigation."
Guindon noted that police work on the case has been completed and criminal charges were filed.
"I can't tell you what happened afterwards," she said.
MMA 5017 played a key role in the sequence of events that saw tank cars filled with volatile crude oil crash and explode last July in Lac-Megantic.
Before the out-of-control train raced toward town, the locomotive was parked for the night uphill from Lac-Megantic. It was left unattended with its engine running to ensure its air brakes remained enabled.
Less than an hour later, the local fire department was called to put out a blaze on the engine, which firefighters turned off.
With the engine still shut down, the train was left unattended once again. Shortly before 1 a.m., the train began to roll toward Lac-Megantic.
Aside from criminal charges, the disaster has also prompted pending civil lawsuits.
Walsh said authorities should have impounded the locomotive in Canada, where they would have been assured control over it.
He also said jurors in an eventual trial may decide to see it.
"A jury is going to want to know that the train that they're looking at is precisely the engine as it was immediately after the accident," he said.
"I was very surprised that it wasn't stored away safely, conserved for the trial."
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