MONCTON, N.B. -- Research into carbine rifles for frontline Mounties was shelved amidst a firestorm of controversy related to the 2007 Tasering death of Robert Dziekanski, an RCMP expert testified Tuesday at the national police force's trial on charges of violating the Canada Labour Code.

The allegations against the RCMP stem from its response to Justin Bourque's 2014 shooting rampage in Moncton, N.B., which claimed the lives of three officers and left two others wounded. Bourque shot each of the officers with a semi-automatic assault rifle.

Police use of the C8 carbine, also a high-powered assault rifle, became a central focus in the fallout from the Moncton shootings. At the time, officers complained they were outgunned by Bourque because they did not have carbines, which have a greater range than the officers' standard-issue pistols.

Testifying in Moncton provincial court, RCMP Supt. Bruce Stuart said he wrote a briefing note in 2006 that recommended the force look at using carbine rifles, but after the deadly stun gun incident involving RCMP officers at the Vancouver International Airport on Oct. 14, 2007, his focus was shifted to conducted energy weapons, such as the Taser.

"It triggered a storm nationally in regards to media and public interest, and I think not only the RCMP, but police agencies across Canada had a general feeling there was a risk of losing a weapon that law enforcement felt was a good tool," Stuart told Judge Leslie Jackson.

"That became the focus of everything we did over the next several years."

Stuart was the first witness to testify at the trial. The charges against the RCMP allege it failed to provide members and supervisors with the appropriate information, instruction and training in an active-shooter event, and didn't give members the appropriate equipment.

Court heard Stuart was later told by an RCMP deputy commissioner that "nothing" had been happening with the carbine issue since the Tasering incident in B.C. and subsequent backlash.

"He basically said there were other priorities and this had fallen off the list of priorities," the 26-year veteran of the RCMP said, adding that the conversation had taken place sometime between 2008 and 2010.

Stuart, a certified carbine instructor, said calls for members to be armed with long guns rather than pistols came after a 2006 shooting in Spiritwood, Sask., in which two Mounties were killed by rifle fire.

He said a 2010 report by an independent researcher found there was a firearms capability gap that needed to be remedied.

Stuart, who helped research that report, said it found in the case of Spiritwood, officers felt ill-equipped to take on someone wielding a rifle.

C8 carbines were eventually approved by the RCMP's senior executive committee in September 2011, more than two and a half years before the Moncton shootings, Stuart testified.

He said the carbines would start rolling out in a year and that threat assessments would be conducted to determine which RCMP divisions would receive them first. He later said that, in his opinion, he would have proceeded with a national rollout.

Crown prosecutor Paul Adams is expected to continue questioning Stuart on Wednesday.

Adams has said the majority of the officers in Moncton who responded to the active-shooter call on June 4, 2014 lacked full training and requalification in firearms.

In his opening comments Monday, Adams said some of the fatalities could have been avoided had the force complied with labour laws.

Retired assistant commissioner Alphonse MacNeil, who issued 64 recommendations in the wake of the Moncton shootings, has said the carbine could have made a difference in that incident and they should be rolled out faster.

Earlier this year, the force said it has completed 42 of the 64 recommendations in MacNeil's 2015 report.

It said more than 3,300 RCMP officers across Canada had been trained to use of the carbine, and that number is expected to double over the next year.