A publication ban has been lifted on the names of six witnesses who allegedly said then Conservative Party staffer Michael Sona bragged to them about arranging a misleading robocall in Canada's 2011 federal election.

The witnesses filled in the blanks in an Elections Canada investigation into the misleading calls in Guelph, Ont., on the May 2, 2011, election day. The calls allegedly tried to direct Liberal and NDP supporters to the wrong polling station.

Their names were initially subject to a publication ban, which CBC News, the Ottawa Citizen, Postmedia and other news outlets fought.

The witnesses are:

Tyler Barker, who works for Senator Carolyn Stewart Olsen, a former director of communications for Prime Minister Stephen Harper.

Mitchell Messom, a former Conservative Party intern who also worked for Stewart Olsen and in 2011 for Steven Fletcher, then democratic reform minister of state. Messom now lives in Nova Scotia.

Rebecca Docksteader, who at the time worked for Conservative MP Chris Warkentin, and now lives outside Edmonton.

John Schudlo, who currently works for Warkentin. He and Docksteader both worked for Warkentin when the alleged conversation with Sona took place.

Benjamin Hicks, who used to work in the Prime Minister's Office and was president of the University of New Brunswick Conservatives. Hicks's name was raised in the Senate in 2010, when he was working in the PMO, after he posted on Facebook a call for students to blow the whistle on "lefty" teachers and professors bringing politics into the classroom.

Conrad Johnson, who formerly worked for Senator Doug Finley and started a job in government relations at Fasken Martineau, the same firm where former Harper chief of staff Guy Giorno is a partner, a few months after speaking to Elections Canada.

The judge lifted the ban Friday morning after hearing arguments by a lawyer representing the media outlets, as well as Sona's lawyer, and the Crown on Wednesday.

Sona is the only person charged in the case. He had worked for Guelph Conservative candidate Marty Burke in the lead-up to the 2011, election, and went on to work for Conservative MP Eve Adams.

Investigator fears witness harassment

Sona hit Twitter to note the lifting of the publication ban. His lawyer, Norm Boxall, agreed to the release of the information, despite initially requesting a ban on the affidavit filed by Al Mathews, the lead investigator for Elections Canada.

"You lost today, Prosecutor. Better get used to it," he tweeted at the Crown assigned to his case, Croft Michaelson.

He also tweeted the names of five of the six witnesses, excluding Barker, who Mathews said was reluctant to talk to him. Sona included a link to a song called Nightmare, by Avenged Sevenfold.

"It's what I've been having to deal [with] for last year. And now they're exposed to the same public scrutiny," he said in an exchange with a reporter who asked about the tweet.

Sona is charged with wilfully preventing or endeavouring to prevent a voter from casting a ballot.

Mathews told the court earlier this week that he thought the names of the witnesses should be protected until the case goes to trial.

He testified that some of the witnesses had told him they feared any media attention would affect their job prospects. He also said he feared they would be harassed by the public or the media.

Judge Célynne Dorval said in her decision that the Crown didn't present any evidence to support those contentions.

Part of the ban, dated Aug. 26, 2013, was lifted in September. Most of the remaining ban was lifted Wednesday after the Crown and Sona agreed to the release of the information.

New details revealed in testimony

Mathews revealed new details about the case in his cross-examination by a lawyer representing the media outlets.

Docksteader, who now uses her married name Carleton, was set up with Mathews via the Conservative Party's then director of communications.

Mathews testified that he wasn't aware of three of the six witnesses who went on to tell him that Sona had told them how he had arranged the robocall.

Conservative Party lawyer Arthur Hamilton approached him about Messom, Docksteader and Schudlo, Mathews said. Docksteader, Mathews recounted, had had concerns about what Sona had told her, and went to Chris Warkentin, the MP for whom she worked with Schudlo at the time.

Warkentin, Mathews says, told Docksteader to speak to Fred Delorey, then in charge of the Conservative Party's media relations. Delorey in turn passed Docksteader to Hamilton, Mathews said.

Warkentin didn't immediately respond to an email asking why he sent Docksteader to Delorey.

Mathews interviewed five of the six in March and April 2012, starting a month after the first media reports about the investigation into the robocalls.

Hicks provided a written statement in which he said Sona "gleefully boasted" about the chaos the robocalls likely caused at the Liberal candidate's headquarters.

Hamilton was present for all the interviews.

Jenni Byrne: 'hold off' on interview

CBC News has also confirmed a report that Jenni Byrne, now Harper's deputy chief of staff, told a possible witness not to speak to Elections Canada until she'd consulted a lawyer.

The Ottawa Citizen and Postmedia reported Friday that Andrew Prescott, who was the deputy campaign manager in the Conservatives' 2011 Guelph campaign, emailed a local Conservative official to say Mathews wanted to speak to him.

Prescott's email was forwarded to Byrne, who responded on Nov. 30, 2011.

“Please hold off doing anything until I consult with a lawyer,” Byrne wrote, a person who saw the email confirmed to CBC News.

Byrne was the party's director of political operations at the time. She was also the Conservative Party's national campaign director for the 2011 election.

Prescott declined to comment on the report. Byrne didn't immediately respond to a request for comment.

Mathews started investigating the misleading robocalls a few days after the 2011 election. Prescott initially spoke to him on a teleconference with Hamilton on Feb. 24, 2012 — three months after Byrne's email — and by early March had found a Guelph-based lawyer to represent him.

Prescott provided Mathews with an email from him to Sona and campaign manager Ken Morgan that provided the pair with the private client login and phone number for RackNine, the company whose system was used to make the misleading calls.

Prescott hasn't spoken to Elections Canada since retaining independent counsel.

Prescott has said he had nothing to do with the misleading calls.