The head of the Manitoba Association for Rights and Liberties says 23-year-old ISIS supporter Aaron Driver should be charged or released from jail immediately.
Driver has been in custody for a week and RCMP are seeking a peace bond as they fear he will participate in terrorism, but so far no charges have been laid.
But that's what concerns civil rights advocates.
"It should shock every Canadian citizen that this is possible or that is being done," Corey Shefman told CBC News.
"I think it's a Tom Cruise movie — Minority Report — where they arrest people for crimes people might commit in the future and that's really what this is like to me. This situation we see here is a violation of our most basic legal right."
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Shefman, who is also a practicing lawyer, says under the Canadian Charter of Rights and Freedoms, Canadians have the right not to be arbitrarily detained.
With Driver's next court date June 24, he will have been in custody for three weeks.
"I cannot comment on what he might or might not do, or what he has or hasn't done. But I do know he hasn't been charged with a crime and yet he finds himself behind bars without his freedom and no reason he has officially been presented with," Shefman said.
"The RCMP are asking for a peace bond which is basically a promise from Mr. Driver to behave himself," he said. "The problem is that he hasn't not behaved himself according to the law at this point."
Under Canada's new Anti-terrorism Act, also known as Bill C-51, people can be charged with the promotion of terror. Shefman said at this point, that's a separate issue because Driver has yet to be charged at all.
Driver's only recourse right now, according to Shefman, is to be released on bail.
The Manitoba Association for Rights and Liberties is also stepping in to the case. Although it is not a personal advocacy group, Shefman said because of the public interest and high-profile nature of Driver's case, he has sent a letter to the federal justice minister expressing concern over what he calls a 'violation' of freedom.
"When we're walking down the street, going about our daily lives...in the past we were able to be confident knowing unless we were charged with a crime we weren't going to lose our freedom," Shefman said. "That's not so clear any more."