What is the common law right of a property owner to exclude persons?

I wish to come full circle in the analysis of the common law right of a property owner to exclude persons. In Harrison v. Carswell, the leading case in the area of trespass law, a powerful dissent was penned by Laskin C.J. which resiled from the opinion of the majority. In this dissent he was joined by Spence and Beetz JJ. He framed the issue in this way (pp. 4-5): “An ancient legal concept, trespass, is urged here in all its pristine force by a shopping centre owner in respect of areas of the shopping centre which have been opened by him to public use, and necessarily so because of the commercial character of the enterprise based on tenancies by operators of a variety of businesses. To say in such circumstances that the shopping centre owner may, at his whim, order any member of the public out of the shopping centre on penalty or liability for trespass if he refuses to leave does not make sense if there is no proper reason in that member's conduct or activity to justify the order to leave. Trespass in its civil law sense, and in its penal sense too, connotes unjustified invasion of another's possession. Where a dwelling house is concerned, the privacy associated with that kind of land‑holding makes any unjustified or unprivileged entry a trespass, technically so even if no damage occurs. A court however would be likely to award only nominal damages for mere unprivileged entry upon another's private premises where no injury occurs, and it is probable that the plaintiff would be ordered to pay costs for seeking empty vindication. The considerations which underlie the protection of private residences cannot apply to the same degree to a shopping centre in respect of its parking areas, roads and sidewalks. Those amenities are closer in character to public roads and sidewalks than to a private dwelling. All that can be urged from a theoretical point of view to assimilate them to private dwellings is to urge that if property is privately owned, no matter the use to which it is put, trespass is as appropriate in the one case as in the other and it does not matter that possession, the invasion of which is basic to trespass, is recognizable in the one case but not in the other. There is here, on this assimilation, a legal injury albeit no actual injury. This is a use of theory which does not square with economic or social fact under the circumstances of the present case. What does a shopping centre owner protect, for what invaded interest of his does he seek vindication in ousting members of the public from sidewalks and roadways and parking areas in the shopping centre? There is no challenge to his title and none to his possession nor to his privacy when members of the public use those amenities. Should he be allowed to choose what members of the public come into those areas when they have been opened to all without discrimination? Human rights legislation would prevent him from discriminating on account of race, colour or creed or national origin, but counsel for the appellant would have it that members of the public can otherwise be excluded or ordered to leave by mere whim. It is contended that it is unnecessary that there be a reason that can stand rational assessment. Disapproval of the owner, in assertion of a remote control over the "public" areas of the shopping centre, whether it be disapproval of picketing or disapproval of the wearing of hats or anything equally innocent, may be converted (so it is argued) into a basis of ouster of members of the public. Can the common law be so devoid of reason as to tolerate this kind of whimsy where public areas of a shopping centre are concerned?”