Screening staff found the device but — in an admitted foul-up — didn't immediately call RCMP and allowed the 18-year-old passenger to board a plane to Mexico with his family for a holiday.
While recent news of the incident has sparked calls for changes to Canada's airport security system, the judge who handled the case had her own stern words for the young bomb-maker.
"If the authorities had missed that pipe bomb and you had gone in Mexico, through a screening device, you would not even get a trial," said provincial court Judge Marilyn White in a court hearing last month. A transcript of the hearing was released Thursday.
"You would be in a Mexican jail. And your grandfather and your family would be visiting you in that jail. And you would probably be learning Spanish by now, if you survived.
"I doubt you would have survived."
Court heard Murphy, now 19, is a high school drop-out and assistant deli manager at a grocery store in Spruce Grove, just west of Edmonton.
He told the judge he researched how to build the pipe bomb on the Internet. He swiped some bullets from his mother's fiance, an Alberta sheriff, to get gunpowder. A friend supplied the fuse and then they bought the rest of their supplies from a hardware store.
Murphy said he put the bomb in his camera bag because he planned to take pictures when they blew up the shed.
It's unclear if that ever happened, but court heard Murphy was clearly surprised when screening staff at the airport pulled the device out of his bag on Sept. 20.
The 15-centimetre-long pipe had threaded caps on the ends and a fuse nearly three metres long. It was filled with black powder.
A source has told the CBC and Edmonton Journal that a screening employee tried to give Murphy back the bomb, but the teen said he didn't want it and it was confiscated. He then proceeded through security and got on his plane.
Four days later, security staff notified RCMP about the find. Mounties arrested Murphy on Sept. 27 at the airport, following his return flight home. Explosives experts had determined the device was a functioning bomb.
Murphy pleaded guilty Dec. 5 to possession of an explosive device. He was sentenced to one year probation, fined $100 and ordered to make an in-person donation of $500 to the University of Alberta Hospital's burn unit.
The judge said Murphy made a "colossal error in judgment" for making the bomb and forgetting it in his luggage.
"Often you see bags and bags of items that people forgot to take out of their carry-on luggage because they just forgot. But I have to say, forgetting a pipe bomb is something bigger than a pair of scissors for your nails," White said.
"Pipe bombs are used to kill people, to destroy property. They are used in war. They are used by terrorists ... They are very successful at killing people."
The Canadian Air Transport Security Authority has said screening staff didn't follow protocol in the case. They should have immediately called on-site RCMP officers, who would have decided whether to arrest Murphy and keep him off the plane.
CATSA spokesman Mathieu Larocque wouldn't confirm if an employee tried to give the bomb pack to the teen. He called it an isolated incident and said the staff involved have been disciplined and re-trained.
Edmonton MP Laurie Hawn, who sits on the Canada-US Permanent Joint Board on Defence, said he was flabbergasted by "such abject failure of common sense."
He believes the workers involved should have been fired and he wants to see CATSA review everything, including recruitment, training, supervision and salaries.
CATSA says there are about 5,000 screening staff at Canada's airports.
They don't make enough money, they don't get enough training and there's constant turnover in the business, said Peter St. John, a security expert in Winnipeg who has been pushing for an entire overhaul of Canada's airport security system.
He's says the case of an irresponsible teenager has highlighted the need for improvement before there's a serious, deadly incident.
Federal Transport Minister Lisa Raitt said in a statement earlier this week that the Edmonton case was "unacceptable" and she planned to talk soon with the president of CATSA.
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