False information about the suspects in Sunday's mosque shootings circulating on the internet has raised new questions about how to fight the explosion of "fake news."

But there are no easy answers on how to stop the spread of lies and misleading news on the web.

The Supreme Court of Canada struck down a law that banned "spreading false news" in the case of Holocaust denier Ernst Zundel in 1992. It remains as Section 181 in the Criminal Code — a so-called zombie law that can't be enforced. But some believe a new, narrower law could be enacted.

"Legislators would have to discuss what kinds of harms we are concerned about and the provision would have to be tightly tailored to that purpose," said Jula Hughes, a law professor at the University of New Brunswick.

"For example, spreading false news for the purpose of interfering with free and democratic elections might be such a harm, and a prohibition that targets this type of false news specifically might arguably pass constitutional muster in the sense that it pursues a valid purpose."

Any prohibition would need to clearly distinguish between political views and news, said Hughes, who expects courts would be leery of any law that could effectively ban publishing opinions.

Canadian lawmakers are now grappling with the issue, studying policy options as part of a sweeping review of Canada's fast-changing news media industry.

Impact on free speech?

But Toronto media lawyer Peter Jacobsen said it would be dangerous to go down a legislative path, because trying to regulate fake news could have the unintended consequence of curtailing free speech.

As it stands, there is no law prohibiting the dissemination of incorrect information unless it is defamatory and covered by libel laws.

There is mounting pressure on social media giants like Twitter, Google and Facebook to show moral responsibility and take steps to limit fake news. The Canadian Press reported last month the companies are working on tools that would help identify and verify information and curb the spread of fake news.

But Jacobsen said private companies can't possibly police the explosion of feeds to weed out wrong information, which is often posted through anonymous accounts.

"It all boils down to who is going to be the arbiter of what's true?" he said. "It sounds simple when you're talking about something that's truly ridiculous, but the same process has to be applied to the truly ridiculous and what is closer to the line in terms of what's true or not."

Calling out errors

Court orders can be used to remove material or award damages when it is found to be defamatory, but that can be costly and time-consuming. Jacobsen said publicly calling out the errors can be an effective tactic.

Prime Minister Justin Trudeau's director of communications Kate Purchase took that approach with Fox News this week, publicly demanding the network delete a tweet that incorrectly reported the suspect in the mosque shooting was of "Moroccan origin."

Thank you <a href="https://twitter.com/FoxNews">@FoxNews</a> for deleting the tweet. We appreciate it. —@katepurchase

Amid the chaos in the initial hours after the shooting, incorrect information was also reported by a number of Canadian news organizations, including CBC News, which was later corrected.

The Daily Beast reported bad information about the mosque suspects, duped by a parody Twitter account that published a hoax claiming to expose the shooters as two "white supremacists."

The fake account is known as @ReutersBrk, which the Daily Beast incorrectly sourced as "Reuters."

Andy Bichlbaum, of the activist duo The Yes Men, created by Jacques Servin (Bichlbaum) and Igor Vamos, said fake news has been used for years, with corporate advertisements masquerading as news. But it took on "horrifying" new heights during the presidential race.

With a mission statement that says '"lies can expose the truth," Bichlbaum said The Yes Men's fake news aims to raise awareness and enact social change, including a hoax on the BBC in 2004 where he pretended to be a representative of Dow Chemical.

The story was quickly exposed as fake, but it created a huge global splash drawing enormous attention to the company's role in an industrial gas leak disaster.

Illuminating vs. manipulating public

Bichlbaum makes a distinction between fake news that aims to expose misdeeds and the proliferation of "sinister," deliberate fake news that aims to manipulate public opinion.

He believes there is a way for policy makers to clamp down on harmful fake news without infringing on free speech.

Google and Facebook have signalled they will take steps to curb the spread of fake news. (Kim Jin-a/Associated Press)

"I'm sure there is a way to distinguish between the two," he said by phone from New York. "You can't make hoaxes illegal, but there's got to be some way to determine if the hoax is intended to mislead the public or to illuminate things for the public. There has got to be a way to do that."

It's not clear what policy options could be on the table in Canada, but Heritage Minister Mélanie Joly believes a healthy, robust news media is part of the solution.

Her spokesman Pierre-Olivier Herbert said the government understands the importance of a "vibrant, local and reliable news media ecosystem" as the media face industry-wide challenges. He noted that 60 per cent of millennials in Canada use social media as their source of news.

"The proliferation of fake news is one of the many disruptions brought on by the digital shift," he said. "The minister has led conversations at home in the context of the consultations on Canadian content and abroad to discuss the relevance of government action in supporting local, reliable and credible sources of information for Canadians. Minister Joly will continue to engage in conversations with relevant platforms on this matter."

'Big problem'

NDP MP Pierre Nantel, vice-chair of the heritage committee studying media industry, called the explosion of fake news a "big problem."

"We need to intervene on this, and the government needs to make sure there are actual resources that have led to great stories like in the movie Spotlight. We have to make sure these sources of information remain valid and remain in business," he said.

Nantel said one way government can help is by using its advertising budget on bona fide news outlets.