The outcome of what's believed to be the first criminal harassment case in Canada involving Twitter will help set the tone for how the courts and society navigate the nuances of online interaction, observers said Thursday.

A verdict is expected Friday in the Ontario Court of Justice trial of Gregory Alan Elliott, a Toronto man facing two charges of criminal harassment over his dealings with two local women's rights activists on Twitter.

Stephanie Guthrie and Heather Reilly have said they feared for their safety, testifying at trial they believe Elliott kept tabs on them and their whereabouts through social media, even after they blocked his account.

This is one of the cases that's out there that, cumulatively, is going to help decide how our society deals with issues like this. - David Grossman, civil lawyer

Elliott's lawyer, Chris Murphy, instead characterized the Twitter interactions — which escalated over months in 2012 and saw both sides trade barbs — as "an ugly political debate" and stressed his client never threatened or made sexual comments to the women.

The Criminal Code prohibits anyone from knowingly or recklessly harassing another person through conduct that causes them to reasonably fear for their safety.

However, those lines have yet to be clearly defined when it comes to online discourse, said David Grossman, a Montreal-based civil lawyer who has dealt with free speech and defamation issues.

"I think a lot of people have been attracted to this case because it is raising issues that we've seen for a while but in a very new context, this context of Twitter and Web 2.0," he said.

While Friday's verdict won't "determine for all of our future how people interact with social media," it will mark a first step in clarifying what's deemed acceptable online behaviour, he said.

"This is one of the cases that's out there that, cumulatively, is going to help decide how our society deals with issues like this," he said.

"There's certainly a message that's going to be sent out, one way or the other, and it will be interesting to see what that message is and how people interpret that and how people react afterward."

Freedom of speech concerns

Cara Zwibel of the Canadian Civil Liberties Association said that regardless of the outcome, the case has already raised concerns about freedom of speech.

"There's nothing wrong with people getting the message that they should think about what they're saying online before they do it, and that they need to exercise discretion and be responsible about what they say," she said.

"There is a concern that when people are engaged in debates and discussions on sometimes highly contentious and controversial issues, they have to be concerned about a criminal charge," she said.

"When the courts are looking at where you draw that line, I think we always need to be balancing the concern for freedom of expression in a pretty substantial and significant way."

Michael Karanicolas, senior legal officer for the Centre for Law and Democracy, said the case is a high-profile example of the courts "feeling their way out" of the issue of online speech.

But he said it's important not to give too much weight to a single court decision, since similar cases are sure to follow, he said.

Defendant arrested in 2012

Elliott was arrested in November 2012 after Guthrie filed a complaint with police.

Court heard communication between Elliott and the two women soured after he criticized Guthrie for publicly calling out a 24-year-old Sault Ste. Marie man who made a video game that instructed players to punch the feminist media critic Anita Sarkeesian repeatedly in the face.

By August of that year, both Guthrie and Reilly had blocked him on Twitter, meaning he could not see their tweets while logged into the social media network and they could not see tweets where he mentioned them by their handle, court records show.

The following month, Elliott tweeted at Guthrie to stop harassing him with accusations of harassment. Guthrie also tweeted at him, telling him to stop harassing her and smearing her work. Reilly tweeted that same day asking Elliott to leave her alone.

Though Elliott did not tweet at either of them for some time, he participated in heated online discussions in which the women were involved.

Murphy has argued that had the women truly been afraid, they would not have continued to "taunt" his client online. But the prosecution has said the women were entitled to fight back against their alleged harasser.

The Crown declined to comment on the case Thursday, as did Reilly. Guthrie did not immediately respond to an interview request.