For the sake of discussion, under what laws should the judge be using? The following is directly out of the canadian criminal code. If the majority of people wish to change the law to allow excessive force then the law should be changed. Until then the judge can only work within the law.
Defence of Property
Defence of personal property
38. (1) Every one who is in peaceable possession of personal property, and every one lawfully assisting him, is justified
(a) in preventing a trespasser from taking it, or
(b) in taking it from a trespasser who has taken it,
if he does not strike or cause bodily harm to the trespasser.
Assault by trespasser
(2) Where a person who is in peaceable possession of personal property lays hands on it, a trespasser who persists in attempting to keep it or take it from him or from any one lawfully assisting him shall be deemed to commit an assault without justification or provocation. R.S., c. C-34, s. 38.
Defence with claim of right
39. (1) Every one who is in peaceable possession of personal property under a claim of right, and every one acting under his authority, is protected from criminal responsibility for defending that possession, even against a person entitled by law to possession of it, if he uses no more force than is necessary.
Defence without claim of right
(2) Every one who is in peaceable possession of personal property, but does not claim it as of right or does not act under the authority of a person who claims it as of right, is not justified or protected from criminal responsibility for defending his possession against a person who is entitled by law to possession of it. R.S., c. C-34, s. 39.