Collett v The State of Western Australia

Collett lodged an application for leave to appeal a decision regarding his parole eligibility. The State of Western Australia opposed the application. The central issue in this case was whether the amendments to the parole eligibility criteria could be applied retrospectively, affecting Collett's eligibility. The applicant argued that the amendments should not be applied retrospectively, while the respondent maintained that the changes were procedural and could be applied retroactively. The court considered the nature of the amendments, their impact on substantive rights, and the principles of legality and fairness.

The court acknowledged that the amendments to the parole eligibility criteria constituted a change in substantive law, affecting the rights of individuals like Collett. It recognised the principle of legality, which mandates that changes in the law should not be applied retrospectively unless explicitly stated. The court examined the purpose and effect of the amendments, concluding that they altered the criteria for parole eligibility in a manner that affected substantive rights. Consequently, the court ruled that the amendments could not be applied retrospectively, thereby affecting Collett's eligibility under the previous criteria.

Given the findings, the court granted the application for leave to appeal and allowed the appeal. It determined that Collett's eligibility for parole should be assessed based on the criteria in place at the time of his offence. The court ordered that Collett's parole eligibility be reviewed and determined according to the original criteria, ensuring that the amendments were not applied retroactively. This decision reinforced the importance of protecting individuals' rights and ensuring that changes in the law are applied fairly and justly.