A primary rule that’s taught in kindergarten: don’t throw stones. Apparently, some people didn’t get the message.

A primary rule that’s taught in kindergarten: don’t throw stones. Apparently, some people didn’t get the message.

Justin Trudeau, security officers and journalists were pelted with a handful of gravel on Monday as the Liberal Party leader campaigned in London, Ont. It’s an alarming escalation by the angry anti-vaccine protesters who have greeted Mr. Trudeau with raised middle fingers and chanted obscenities at his recent campaign stops.

Mr. Trudeau sought to downplay the incident: "There was little bits of gravel. It’s no big deal."

With respect, it is a big deal. A robust democracy embraces many methods of protest, but when Canada’s elected leader is assaulted with pitched projectiles, that’s over the line.

The bounds of civility are not always clear in the emotional heat of protests. What separates permissible protests from improper aggression such as Monday’s stone-throwing debacle?

To begin with, physical assault is always unacceptable, even if the stones tossed are small. Protests must stop short of potentially injuring other people.

Accordingly, protests last week that hindered functions at several hospitals across Canada, including Winnipeg’s Health Sciences Centre, were deplorable because people could have been harmed. Ambulances were impeded while delivering patients to the emergency department and other individuals opted to skip appointments rather than risking the wrath of protesters, meaning patients’ medical conditions could have worsened.

Attempts to gauge the legitimacy of protest tactics get less clear, and more subjective, when the damage is to property and not to people.

Take, for example, the sculpture in front of the Pantages Playhouse Theatre on Main Street, which commemorates protesters overturning a streetcar in 1919. The iconic act was vandalism by any legal definition, but it is widely celebrated because the streetcar was upended during the Winnipeg General Strike, and the vandalism became a symbol of workers united in the struggle for a better life.

In the same grey area involving destruction of property during protests, the Manitoba Legislature currently has two empty plinths where statues of Queen Victoria and Queen Elizabeth stood until Canada Day, when they were toppled during a protest honouring victims of residential schools established by colonial decree. It’s illegal to destroy public statues, but police have not laid criminal charges.

Obviously, protests that break laws in the interests of social justice are sometimes overlooked by authorities, who presumably have an ear to the ground of widespread public sentiment. Central to the issue, however, is who decides — the authorities, not the protesters — whether lawlessness has a moral basis that makes it worthy of leeway.

JOHN WOODS / WINNIPEG FREE PRESS</p><p>PPC Leader Maxime Bernier speaks in Winnipeg on Sept. 6.</p>


PPC Leader Maxime Bernier speaks in Winnipeg on Sept. 6.

Just ask Maxime Bernier. The leader of the People’s Party of Canada might believe his rejection of public-health orders has a moral basis and is a social-justice issue, but it’s not his decision to make. Manitoba RCMP charged him in June under the Public Health Act for an illegal assembly and for failing to self-isolate once he got to Manitoba.

His brief time-out in Winnipeg apparently had little impact. He returned to Manitoba this week, and continued to openly violate public-health orders.

As Mr. Bernier is considered a prominent leader among Canada’s anti-vaxxers, some people might regard it as fair turnaround that he was struck by a (presumably) pro-vaxxer-tossed egg at an event last week. As was the gravel thrown at Mr. Trudeau, however, such an expression of disagreement must be condemned in no uncertain terms.

Remember the childhood lesson: throwing stones (or eggs, or anything else) is unacceptable, regardless of the target.