For a long time, union activity took place underground, outside the law. Looking as far back as possible into the history of labour relations, criminal law and private law condemned the collective pressure tactics used by employees. This situation greatly contributed to the belief, still widely held in some union circles, that the courts are unfavourably biased against trade unions. It is essentially through political mobilization and action that trade unions, in the mid-20th century, finally obtained recognition under the law of the right to bargain collectively for their working conditions and the right to use pressure tactics to this end. Although the interests of employees have generally been well served by the legal system, legislators have, at times, intervened to limit the capacity of trade unions to bargain collectively for their working conditions or to use pressure tactics against employers. Following the adoption of the Canadian Charter of Rights and Freedoms, some trade unions endeavoured to limit such legislation in the name of their constitutional freedom of association, but without success. Some observers took this as another sign of the legal system's insensitivity to trade unions. However, the Supreme Court of Canada now recognizes that freedom of association includes, at the very least, a procedural right to bargain collectively. Could the Canadian Charter henceforth provide trade unions with a new kind of pressure tactic?