In a series of posts on social media, Cardy called out the police force, asking why the "illegal" gathering is being allowed under the rules of New Brunswick's COVID-19 emergency order and suggesting their enforcement of the law is selective.

The posts began with a tweet on Thursday in response to a Fredericton police news release regarding the planned protest.

The release, posted on Twitter and on the force's Facebook page, noted that police are "aware of the planned rally" scheduled for Saturday afternoon at Fredericton City Hall.

"We have connected with the organizers of this event to discuss their intentions and make them aware of the possible consequences to gathering without following current public health measures," the release said, noting that officers will be recording the event via the force's drone and body-worn video cameras.

"We respect the right to peaceful demonstration, and our goal is to ensure public safety and security for all."

Cardy responded by asking police: "As a Fredericton MLA can you let me know how any sort of gathering is allowed under the Emergency Order, which specifically prohibits them?" 

He later tweeted his phone number and said police should "feel free to call" him to clarify, "along with what other laws are optional in Fredericton if you decide you really don't like them."  

On Friday afternoon, Cardy posted an announcement from the protesters' Facebook page, again calling out the Fredericton police.

"These folks think their rally tomorrow is okay, based on your message from yesterday," he said in a tweet.

"Please clarify that this gathering is illegal, and that there is no way to attend peacefully without risking a fine."

New Brunswick has been at the most restrictive level of its COVID management plan for a week, and it's to stay in lockdown at least until Jan. 30.

The police force has not publicly responded to Cardy's tweets or answered a CBC News request for comment, sent Friday afternoon.

Cardy did not respond to requests for an interview either.

J.P. Lewis, a political scientist at the University of New Brunswick in Saint John, said that Cardy's latest tweets exemplify his unique and 'effective' social media strategy. (CBC)

'Not unusual for Cardy,' political scientist says

But political science professor J.P. Lewis, who teaches at the University of New Brunswick in Saint John, said that a cabinet minister tangling with the police via social media isn't surprising — for Cardy.

"I think generally, we would describe it as unusual for a minister, but I wouldn't describe it as unusual for Dominic Cardy, just in terms of how he uses social media," Lewis said.

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He noted that while cabinet ministers tend to use social media in very scripted and non-combative ways, Cardy has forged his own social-media style.

Cardy, whose pro-vaccination stance has been clearly and publicly established, was engaging in heated social media debates with anti-vaccination groups and individuals long before COVID-19 arrived, he said.

"We know that when the minister decides to turn up the volume politically … this is how he does it. And I think in the sense of bringing attention to it, it is effective," Lewis said.

Meeting protesters on their playing field

Taking his message to Twitter and directly targeting the group or the message he opposes "raises the stakes."

"By getting it out on social media, we know that brings a lot more attention compared to maybe traditional means of a minister releasing a press release saying 'I've contacted the local authorities and I'm concerned,' " Lewis said.

"If you tweet about it, it draws a lot more attention in this day and age."

There's also the advantage, whether deliberate or coincidental, that Cardy is meeting these groups "on their playing field," Lewis said.

Protesters rely on social media, particularly Facebook and Twitter, to spread their message, Lewis said.

"So he's engaging in that arena, basically."