The RCMP believed an Edmonton-area teen’s story that he had no plans to blow up a plane with a pipe bomb he said he unintentionally carried through airport security, because he had a “shocked reaction” when security screeners found the device, according to court transcripts obtained by CBC News.

The RCMP based this belief on surveillance video from the encounter at Edmonton International Airport on Sept. 20 between then 18-year-old Skylar Murphy and security personnel.

“I didn’t view [the video] but [RCMP investigating officer] Constable [Jim] Kirkpatrick described to me, he said it was obvious on the surveillance video, when the object was pulled out of his bag, the shocked reaction he had,” Crown prosecutor Trent Wilson told the court at Murphy's hearing on Dec. 5.

The court also heard testimony from the teenager that he obtained the gunpowder by stealing bullets from his mother’s fiancé, an Alberta sheriff. It is not now known if the bullets were from the sheriff’s service weapon.

Skylar Murphy, in a photo believed to be from 2011, inadvertently brought a pipe bomb to the Edmonton International Airport. (Facebook ) Alberta Justice said the sheriff did no wrong.

"The independent RCMP investigation determined the sheriff had no knowledge of or role in constructing the device," a spokesperson said in a news release Thursday. "The sheriff properly and lawfully stored his firearms and ammunition as per federal law and policies of the sheriff’s branch."

The incident has become a national, and international, scandal because, as CBC News learned, the screening guard who seized the pipe bomb from Murphy tried to give it back to him, even though the steel pipe bomb had a fuse attached to it.

RCMP not told about bomb for 4 days

Sources have told CBC News that Murphy insisted the guard take it back. He was then allowed to clear security and board a plane to Mexico where he was travelling with his family on a week-long vacation. The bomb was put aside and the RCMP, inexplicably, was not told about it until four days later.

When he returned from the vacation on Sept. 27, Murphy was arrested by a large number of uniformed officers, a SWAT team and bomb-sniffing dogs.

According to the court transcript, Murphy and a friend built the pipe bomb because they intended to blow up a shed for fun.

“Mr. Murphy also said he wanted to photograph the shed when he blew it up and that was why he had the bomb inside of his camera bag,” the prosecutor told the court.

“When Mr. Murphy packed for his flight, he placed his camera bag inside his carry-on duffel bag. He emphatically denied that his intent was to cause damage to the airport or any aircraft. He claimed that he forgot the pipe bomb was inside his camera bag and he did not intend to try to take it on the airplane.”

Fully functional pipe bomb

The transcript describes how the explosive device was discovered at the airport.

“An object, which was later confirmed by the RCMP explosive disposal unit members to be a fully functional pipe bomb, was first identified by an employee conducting an X-ray inspection of Murphy’s bag,” the prosecutor said.

Murphy confirmed he was the owner of the bag.

“Items were taken out of the bag in front of Mr. Murphy,” the prosecutor said. “The object was inside a small cloth bag and was made out of a 5½-inch long metal pipe with two threaded end caps. One end of the pipe had a fuse sticking out of it that measured over nine-feet long. The pipe was filled with black powder.

“The pipe bomb was not given back to Mr. Murphy and he was allowed to board his flight to Mexico,” the prosecutor told the court. The transcript makes no reference to the security screener attempting to return the pipe bomb to Murphy.

The prosecutor asked the judge to impose a one-year, suspended sentence for Murphy's guilty plea of being in possession of an explosive device, which the judge granted. He also fined Murphy $100 and ordered him to donate $500 to a burn unit.

Murphy offered to tell his story to CBC News on the condition it would cover his $600 in penalties. CBC turned down the offer.

Judge scolds teen

In sentencing Murphy, the judge scolded the teenager for stealing from his mother’s fiancé and for his bad judgment in producing such a dangerous device.

“Pipe bombs are used to kill people, to destroy property, they are used in war, they are used by terrorists, they are used by individuals who are in conflict, and they are very successful at killing people,” the judge told Murphy.

The judge also told the teen that had he carried the pipe bomb to Mexico, he might be facing a very different fate.

“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, more than likely,” the judge said. “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.”

Sources have told CBC News that the security screeners were from the private company Garda, which provides security screening at the airport under contract to the Canadian Air Transport Security Authority (CATSA). It is not known when CATSA officials became aware of the bomb or why it took four days to report it to the RCMP.

One source told CBC News that the screener tried to return the pipe bomb to Murphy because the screener simply did not recognize what it was. The source said the fact the screener did not recognize a pipe bomb is indicative of the general poor state of training of airport screeners.

The source said that after the pipe bomb was discovered, the airport should have been immediately evacuated because of the high risk of injury and death to the public.