Picketing — Ontario Employment Law

In Ontario, picketing is a highly visible and heavily regulated aspect of labour disputes, typically occurring during a lawful strike or lockout under the Labour Relations Act, 1995. At its core, picketing involves workers gathering outside a workplace—often alongside signs or banners—to communicate their position, persuade others not to cross the picket line, and cultivate public sympathy. While picketing is a fundamental tool for organized labour, it inherently creates friction between the striking workers' constitutional rights and the employer's right to protect its property and continue operations.

Ontario courts recognize that peaceful picketing is a protected form of freedom of expression under the Canadian Charter of Rights and Freedoms. Workers are legally permitted to patrol the perimeter of their workplace, disseminate information, and attempt to persuade suppliers, customers, and other employees to join their cause. However, this right is not absolute. The law draws a firm line between peaceful persuasion and unlawful interference. Picketing becomes illegal if it crosses into tortious or criminal conduct, such as violence, intimidation, trespassing, vandalism, or completely obstructing access to the employer's premises.

When a picket line escalates from mere communication to effectively shutting down business operations by trapping vehicles or blocking entrances, employers routinely seek intervention from the courts. Rather than applying to the Ontario Labour Relations Board, employers typically bring an application to the Superior Court of Justice for an interlocutory injunction. To secure an injunction, the employer must provide detailed affidavit evidence demonstrating that the picketers' conduct is unlawful, that it is causing irreparable harm (such as severe economic loss or threats to public safety), and that police intervention has been insufficient or is impractical.

If the court agrees, it will typically issue an order strictly limiting how the picketing can be conducted—for example, by restricting the number of picketers allowed at each gate or specifying how many minutes picketers can delay a vehicle before letting it pass. Because the specifics of every labour dispute differ, resolving where protected expression ends and unlawful obstruction begins requires careful legal analysis of the facts on the ground.