A second attempt to hold parliamentary hearings on the collapse of the criminal case against Vice-Admiral Mark Norman was successful late Tuesday, as a handful of Independent senators voted in favour of a Conservative motion to hear him testify.

The motion, put before the Senate defence committee, calls on it "to examine and report on the circumstances that led the RCMP to lay now stayed criminal charges" against Norman, the military's former second-in-command.

The committee now looks to see the former vice chief of the defence staff, his boss Gen. Jonathan Vance and Defence Minister Harjit Sajjan called to testify before June 20, when Parliament is widely expected to rise for the final time before the fall election.

The committee will have to meet again to decide when that testimony will be heard.

On Wednesday, Sajjan said he is "always happy to participate in the Parliamentary process" and that he's spent considerable time already testifying before the Senate.

"The Senate has the ability and right to be able to study any subject that they want," Sajjan said. He added the federal government stayed out the legal process until it had run its course, at which point he "reassessed the criteria for reimbursements," a reference to the government offering to pay Norman's legal fees.

He said it will be up to Vance to decide when Norman returns to work and in what capacity.

The Crown withdrew a charge of breach of trust against Norman, who was accused of leaking cabinet secrets related to a $668 million shipbuilding deal in 2015.

Prosecutors said there was no reasonable prospect of conviction after defence lawyers presented them with new evidence, including interviews, that had not been done by the RCMP.

Neither the Crown nor the defence would say what that evidence might be.

It is known that a portion of the Crown's case rested on allegations Norman leaked cabinet secrets under the former Conservative government. But none of the former ministers or political staffers who claim Norman was acting under their instructions in dealing with the Davie Shipyard, in Levis, Que. were interviewed by police.

Senators on both sides of the political divide agreed the case has raised a number of major public policy concerns.

"We have a good platform here to examine what happened to Vice-Admiral Norman and give him an opportunity to explain himself in public," said Conservative Senator Jean-Guy Dagenais, who sponsored the motion.

"I don't understand how you could suspend someone with such a brilliant career for two years.

"I don't understand what the RCMP did during their investigation. We've [now] told Vice-Admiral Norman, 'Don't worry, no more accusations, you can go back to work.'"

House committee declined to investigate

The Liberal-dominated House of Commons defence committee declined to investigate when the question was put to it on May 16. At the time, Liberal MPs said they were not convinced by almost two hours of opposition arguments.

Independent Sen. Andre Pratte said Tuesday that "on principle" he agreed that there should be an investigation, but voted against the motion after saying he had reservations about the odds of completing it before Parliament adjourned.

"It's important," he said. "It should be investigated."

Nova Scotia Liberal Sen. Terry Mercer, who was also on the no side, had a warning for Conservatives who have been clamouring for an investigation: "Be careful what you ask for in this business."

A self-proclaimed friend of Norman, he said he also wanted to know how the country's second most powerful member of the military became caught up in such a scandal, but threatened to call members of the former Conservative government, including cabinet ministers.

"I think there's nothing more partisan than this motion," said Mercer. "We're months away from an election. The object, I would suggest, is for the Conservatives to get this out in front of the public and go on a fishing trip to find something to embarrass the current government."

The importance of Norman testifying before Parliament was underlined by experts a few weeks back, who said that while still in uniform the vice-admiral is governed by military regulations that prohibit him from criticizing both his superiors and the government. But he will be able to speak his mind more freely under under the protection of parliamentary privilege.