What is the test for constitutional vagueness?

Gonthier J. considered the doctrine of vagueness further in Ontario v. Canadian Pacific. In determining whether a particular provision is constitutionally vague, the court must consider whether the provision “…provides a sufficient basis for distinguishing between permissible and impermissible conduct, or for ascertaining an ‘area of risk’” (at 1070). The court should consider whether the law “…provides sufficient guidance for legal debate as to the scope of prohibited conduct” (at 1070). The standard of precision required will vary depending on the nature and subject matter (at 1071). The existence of an identifiable “core” of activity that is prohibited is often an indicator that the law provides sufficient guidance for legal debate (at 1047).