Secondary Picketing Law and Legal Definition

Secondary picketing is the picketing of an establishment with which the picketing party has no direct dispute in order to pressure the party with which there is a dispute. It is picketing at locations other than that of the employer involved in the labor dispute.

Many courts, taking the view that secondary picketing is an unwarranted application of economic pressure against uninvolved third parties, have held that the practice is, illegal. Others, sensing that this approach was unduly harsh towards unions, have attempted to modify the rule of illegality per se by various means, such as refusing to restrain picketing at sites sharing a common corporate ownership with the primary employer and developing an ally doctrine under which the picketing of establishments involved in aiding the struck employer was declared permissible.