The Crown had argued that the witnesses were concerned about being harassed and losing employment opportunities if their involvement in the case against Michael Sona became public.
Sona, a young Conservative worker in the Guelph, Ont., campaign of candidate Marty Burke, is the only person charged to date over fraudulent robocalls made during the 2011 election.
Justice Celynne Dorval had previously lifted a publication ban on the contents of the testimony at the request of media outlets and now says there is no evidence of a risk of harassment.
Sona, who has been charged with "having wilfully prevented or endeavoured to prevent an elector from voting at an election," maintains his innocence and wanted the publication ban lifted.
Of the six named witnesses, three had worked for Conservative MPs; two had worked for Prime Minister Stephen Harper's former communications director, Sen. Carolyn Stewart Olsen; and one had worked in the Prime Minister's Office.
The witnesses who spoke to investigator Al Mathews in the spring of 2012 are: Tyler Barker, Rebecca Dockstaeder, Benjamin Hicks, Conrad Johnson, Mitchell Messom and John Schudlo.