The revelation that actors were hired to attend a Toronto rally this week in support of Progressive Conservative Leader Doug Ford is part of a larger trend that is cause for real concern, say political experts.

This form of political deception, which dates back at least as far as the first century AD, when Nero, the infamous Roman emperor, would regularly pay audience members to clap for his musical performances, arguably peaked some 1,800 years later in antebellum U.S. presidential politics, before largely falling into disuse.

But in recent years, it seems to have made a dramatic comeback.

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The practice, also known as astroturfing — the process of creating an illusion of grassroots support (named after the artificial turf used to replace grass) —returned to public attention during the most recent U.S. presidential election. In 2015, Donald Trump was accused of manufacturing support by paying actors $50 a person to wear campaign T-shirts, hold signs, and cheer when he announced his candidacy.

Now, the allure of “crowds-for-hire” can be seen enticing Ontario political candidates. Conservative officials confirmed Monday that the campaign of Toronto Centre PC hopeful Meredith Cartwright was behind the recent piece of electoral theatre, which the officials described as an isolated “mistake.”

Still, political experts believe astroturfing, in its various forms, is taking root in Canada.

“One cannot assume other than it is already here, and that it will continue to grow until there are serious legislative decisions taken to prevent it,” said Robin Sears, a principal at Earnscliffe Strategy Group, Star columnist and a former NDP strategist of 20 years.

“Our experience (with) election techniques and practices in Canada — going back to when I was starting in this business a long, long time ago — is that we always copy the Americans, usually one election cycle later.”

But Sears said the practice of paying for supporters in the real world is far less prevalent and dangerous than is astroturfing online.

Anonymity granted by social media means campaigns can put their money behind tactics like using online trolls, people who anonymously create accounts and post content with the purpose of pushing an agenda.

Russian trolls dominated the American presidential election headlines in 2016, accused of meddling with the democratic process. In February, 13 Russians were charged with offences relating to their alleged plot to interfere with the presidential election through social media propaganda.

Top executives at Facebook, Twitter and Google have also admitted that the platforms were used by Russia to interfere in the 2016 election.

The purposefully divisive troll posts enjoyed hundreds of thousands of likes and shares, numbers that can easily be amplified through bots, or automatized accounts that run as if they were commanded by a human.

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“The degree that you can multiply the impact of your anonymous attack very cheaply and efficiently is even more troubling,” said Sears. “This is very easy to do on a wholesale level and very hard to be caught doing. I think it is probably the most serious threat to all the democracies around the world.”

Elizabeth Dubois, an assistant professor at the University of Ottawa, studies political bots and the use of automation in campaigns.

“Manipulation of social media versions of public opinion could, given enough spotlight, be very influential,” she said. Her research on the 2015 federal election did not, however, find a major impact of political bots.

She also studied the hashtag #CrookedChristine, deployed during the Ontario PC leadership race to take shots at candidate Christine Elliot, and found that many of the accounts were created within a few minutes of each other, had stock image photos, and their activity was consistent with bot accounts. All of this pointed to astroturfing, she said.

“What we’re seeing, I think, is small scale experiments right now, and I expect that as we get closer and closer to the election, more of these kinds of tactics will come forward,” Dubois said.

Creating online astroturfing armies is an inexpensive tactic compared to generating a paid-for crowd to create the “illusion” of support and play into social pressures, said Tim Abray, a political studies teaching fellow and Ph.D. candidate at Queen’s University.

“The thing that distinguishes this, and sends it into a potential grey area — or even, for someone like me, a red zone — is that these are not actual supporters,” he said. “They’re simply props.”

Abray said the “illusion” created by large crowds plays into social pressures that can influence how people vote. The bandwagon effect, namely making a decision based on a candidates presumed popularity, is something politicians like Trump or Ford are apparently playing into when boasting about the size of their crowds.

In the provincial election, Abray doubts that astroturfing will sway the result because the practice is not widely used here. However, he said researchers will be keeping an eye on whether it begins to take over “traditional, labour intensive tactics” like holding rallies for genuine supporters.

“If we continue to use these sorts of tactics where we wallpaper the universe with manufactured support, it means that people with more money or deeper pockets or better financed campaigns are going to have an easier time,” he said.

“And that’s something that we should be deeply concerned about.”

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