Sona, 25, is accused of concocting an elaborate plot to autodial 6,700 phone numbers in Guelph, Ont., in an effort to steer non-Conservative supporters away from the ballot box on the day of the 2011 federal election.
The Crown's three final witnesses, all of them former colleagues of Sona's, described how the accused returned to Parliament Hill full of bravado after the election, which delivered a Conservative majority government.
He explicitly detailed his every step in the so-called robocalls affair, they said, and even likened his covert operation to an episode of the TV drama "24."
"My impression was he was sort of revelling in it; it gave him a bad-boy vibe, I guess," said John Schudlo, who found Sona's story so outlandish he wasn't sure what details he could believe, if any.
"Mike is a storyteller, and I'm giving him credit in a way, he tells an interesting story."
The defence honed in on an inconsistency in the testimony from Sona's colleagues.
On Wednesday, one witness said Sona seemed proud of every step of the plan: buying a prepaid credit card and pay-as-you-go cellphone, acquiring phone numbers for Liberal supporters, enlisting a telemarketer to execute the calls and dismantling the phone, even scattering its various pieces.
On Thursday, however, Schudlo said Sona told him he didn't act alone.
"(It was) he and someone else, at least one other person; I remember it because I think he was saying 'we,'" Schudlo said.
"Frequently in the conversation he described that 'we' did this or 'we' did that?" asked Sona's lawyer, Norm Boxall.
"Yes," Schudlo replied. He could not remember if Sona mentioned any names, he added.
"If he did — and I've gone through this in my mind and I've tried to remember — but if he did, if he said a name, I wouldn't have known who they were, so it wouldn't have stuck in my mind."
Benjamin Hicks testified he simply couldn't remember if Sona mentioned an accomplice.
But he vividly recalled Sona's boastful admission of working under the gun to accomplish a secret mission, like on "24" — a show about terrorists and secret agents that tells its story minute by minute, complete with the sound of a ticking clock.
"I was very shocked by the whole conversation," said Hicks, who at one point asked Sona if his candidate, Marty Burke, knew what he was up to.
"I distinctly remember him joking, 'Are you wearing a wire?'"
Sona, who has maintained his innocence, is charged with "wilfully preventing or endeavouring to prevent an elector from voting." He faces a maximum penalty of five years in prison.
On Wednesday, court heard from Sona's former friend Andrew Prescott, who was given immunity in exchange for his testimony.
He recalled that sometime on election day, Sona was "almost euphoric" as he emerged from his campaign office cubicle, saying, "'It's working.'" That night, as the team celebrated the party's majority win, Sona gave a toast that included "thanks to Pierre," he added.
The prepaid cellphone linked to the case was purchased with the fake name Pierre Poutine and the account with robocall provider RackNine was registered under Pierre Jones.
Court also heard that Prescott was ordered by campaign manager Ken Morgan to log into the website of RackNine on election day and abort a campaign.
Investigators later determined the account Morgan got Prescott to log in to was the same used to send the Guelph robocalls.
Morgan moved to Kuwait shortly after the 2011 campaign and, according to court documents, has refused to speak to Elections Canada investigators about the robocall affair. He has not been charged with any offence.
The trial is expected to resume Monday with closing arguments.