Brown – Federal Court of Appeal recognizes, but finds inapplicable, a doctrine of statutory voidness for uncertainty

In rejecting a submission of a self-represented taxpayer (er, rather, natural person) that definitions in the Act, such as of "taxpayer" and "business," are so vague as to render the Act null and void, Webb JA quoted with approval a statement in the Supreme Court that "a law will [only] be found unconstitutionally vague if it so lacks in precision as not to give sufficient guidance for legal debate."

Neal Armstrong. Summary of Brown v. The Queen, 2014 FCA 301 under Statutory Interpretation – Resolution of Ambiguity.