The Crown failed to show that the public interest of ridding the roads of bad drivers could be proportional to the limiting of people's rights by imprisoning them.
In surveying means of interpreting the constitution, Lamer dismissed the practice of relying on the testimony of the original drafters of the Constitution as interpretive aids, effectively rejecting the use of an original intent approach to Constitutional interpretation. Reference was made to the living tree doctrine in this regard. The Court also rejected the more restricted definition of fundamental justice under the Canadian Bill of Rights, as described in Duke v. The Queen (1972).
The Court noted that the alternative view of fundamental justice as natural justice would have been an easier requirement for the government to satisfy. This would limit the rights to life, liberty, and security of person, or, as the Supreme Court put it, place these rights "in a sorely emaciated state." Liberty, for example, would be seen as not as comprehensive a right as section 9, which guards against arbitrary arrest and detention. Security of person would also be less comprehensive than section 8 rights against unreasonable search and seizure. Such an interpretation, the Court decided, would be inconsistent with the normal reading of the Charter, demonstrated in Law Society of Upper Canada v. Skapinker (1984) and Hunter v. Southam Inc., which was meant to be generous. For this reason, Lamer added that sections 8-14 should be seen as provided examples of principles of fundamental justice.
Another reason for discarding the Duke interpretation of fundamental justice was the difference in wording between the Bill of Rights and the Charter. In guaranteeing fundamental justice, the Bill of Rights references a "fair hearing." Section 7 does not mention a fair hearing and the only context for fundamental justice is the "much more fundamental rights" of life, liberty and security of person.