## Facts

- A municipality contracted with a private waste-disposal company to dispose of all refuse generated within the city, requiring the contractor to provide a site, labor, materials, and equipment.
- A landfill site was chosen bordering a creek that flowed into a river.
- The landfill method involved compacting garbage in layers and covering it daily with sand or gravel.
- The site contained freshwater springs feeding into the creek; fill was dumped to submerge the springs, and garbage was deposited close to the creek.
- Pollution of the creek and river occurred.
- The contractor was convicted under a provincial water pollution provision prohibiting any municipality or person from discharging, depositing, causing, or permitting the discharge or deposit of material into a watercourse or its shore/bank.
- The municipality was also charged under the same provision based on its role in arranging disposal through the contractor.

## Issues

1. Whether a charge alleging alternative statutory modes of committing the offence (e.g., “discharge,” “cause,” “permit,” “deposit”) was fatally duplicitous and, if so, whether the objection could be raised on appeal.
2. How to classify a public-welfare pollution offence where the statute is silent on mens rea: mens rea (“true crime”), absolute liability, or an intermediate category allowing a due diligence defence.
3. If the offence is not a mens rea offence, what burdens and standards apply to any due diligence defence.

## Decision

- The Court held the pollution provision created a public-welfare offence of strict liability, not a mens rea offence and not absolute liability.
- The Crown must prove the actus reus beyond a reasonable doubt; mens rea need not be proved.
- The accused may avoid liability by proving due diligence on a balance of probabilities, including reasonable mistake of fact or taking all reasonable steps to prevent the prohibited event.
- The duplicity objection did not bar further proceedings on the charge as framed.
- The Court dismissed both appeal and cross-appeal but ordered a new trial so liability could be determined under the clarified strict-liability framework.

## Legal Principles

- Offences fall into three categories: (1) mens rea (“true crimes”), (2) strict liability (actus reus proved by the Crown; due diligence available), and (3) absolute liability (actus reus alone; no defence).
- For public-welfare/regulatory offences where the legislature is silent on fault, courts generally presume strict liability rather than absolute liability, absent clear legislative intent to exclude a due diligence defence.
- In strict liability, the prohibited act is prima facie proof of the offence once actus reus is established; the accused bears the persuasive burden to prove due diligence on a balance of probabilities.
- Due diligence is established by showing either (a) a reasonable mistake of fact that would make the conduct innocent if true, or (b) all reasonable steps were taken to avoid the prohibited event.
- Whether an offence is absolute liability may depend on factors such as the regulatory scheme, subject matter, penalty severity, and statutory language precision.

## Conclusion

The Court defined a tripartite framework for penal liability and held that a regulatory water-pollution offence silent on mens rea is presumptively strict liability, allowing the accused to avoid conviction by proving due diligence; the matter was sent back for a new trial under that standard.


Regina v. City of Sault Ste. Marie, [1978] 2 S.C.R. 1299 (Can.)