In order to protect the principle of competition, valued by all liberal, capitalistic societies, laws or anti-combines laws have been created to prevent and punish the undermining of free markets by corporate combination.
When corporates get together and eliminate competition, there is protection against this in the anti-combines law in Canada and also in the U.S.A. The combines department of the government can investigate and recommend prosecution, with or without complaint.
Canadian Parliament had passed an Anti-Combines Law in 1889, but its actual effect was to legalize price fixing, for the anti-combines law held restraints on trade actionable only if they unduly or unreasonably lessened competition. The flawed Anti-Combines Law seemed a deliberate shot into its own net by a government of vested interests.
The Supreme Court of Canada in Jabour expressly linked the RCD (Regulated Conduct Doctrine) to the then criminal nature of the anti-combines law legislation: So long as the CIA (Combines Investigation Act), or at least Part V, is styled as a criminal prohibition, proceedings in its implementation and enforcement will require a demonstration of some conduct contrary to the public interest.
It is this element of the federal legislation that these cases all concluded can be negated by the authority extended by a valid provincial regulatory scheme.
These comments were based on earlier case law which explicitly tied the availability of the Regulated Conduct Doctrine to the criminal nature of the federal anti-combines law. In particular, the courts have focussed on the undueness standard in the conspiracy provision, a term which has been explicitly equated with the public interest, and have concluded that provincially regulated conduct could not be undue or contrary to the public interest.
Recent Canadian Anti-Combines
Policy: Mergers and Monopoly - Robert Lyon
The University of Toronto Law Journal, Vol. 15, No. 1 (1963), pp. 155-184
Some Empirical Issues in Canadian Combines Policy - J. N. Wolfe
The Canadian Journal of Economics and Political Science / Revue canadienne d'Economique et de Science politique, Vol. 23, No. 1 (Feb., 1957), pp. 113-121
McDonald, Bruce C. "Constitutional Aspects of Canadian Anti-Combines Law Enforcement" (1969).