## Facts

- The accused participated in a maritime scheme to transport a large quantity of marijuana from Colombia toward Alaska, intending to remain outside Canadian territorial waters.
- While off the coast of British Columbia, the vessel developed serious mechanical problems in worsening weather conditions.
- For safety, the captain altered course into Canadian waters to seek shelter and make repairs.
- The vessel grounded in a sheltered cove; to prevent capsizing, the crew offloaded much of the marijuana onto shore.
- Police arrived after most of the cargo had been moved ashore.
- The accused were charged with importing cannabis into Canada and possessing cannabis for the purpose of trafficking under federal narcotics legislation.
- At trial, the accused relied primarily on the common-law defence of necessity, asserting that the peril at sea compelled entry into Canada and offloading.
- The jury acquitted; the provincial appellate court set aside the acquittals and ordered a new trial based on errors in the trial proceedings and instructions.

## Issues

1. Whether the common-law defence of necessity operates as a justification or as an excuse.
2. What elements and thresholds govern necessity, including imminence of peril, the absence of reasonable legal alternatives, and proportionality.
3. Whether the jury instructions on necessity accurately conveyed the required legal test.

## Decision

- The Supreme Court dismissed the accused’s appeal and affirmed the order for a new trial.
- Necessity was recognized as an excuse, not a justification.
- The Court held that necessity is available only in narrow circumstances: clear and imminent peril, demonstrable impossibility of lawful compliance (no reasonable legal alternative), and proportionality between the harm inflicted and the harm avoided.
- The trial judge’s charge, taken as a whole, was too broad and could have led the jury to acquit based on a general reasonableness standard rather than the strict necessity requirements.

## Legal Principles

- Necessity is an excusing doctrine: it does not render the prohibited act socially right; it excuses conduct that was realistically unavoidable in an emergency.
- The defence is confined to urgent situations of clear and imminent peril.
- The accused must show that compliance with the law was demonstrably impossible, meaning there was no reasonable legal alternative to avoid the peril.
- Proportionality is required: the harm caused by the illegal act must not outweigh the harm avoided.
- The doctrine rests on a practical concept of involuntariness assessed against societal expectations of normal resistance to pressure; it must be strictly limited to prevent it from becoming a general permission to break the law.

## Conclusion

The Court confirmed necessity as a tightly confined common-law excuse and ordered a new trial because the jury instructions did not adequately require findings of imminent peril, no reasonable legal alternative, and proportionality before the defence could succeed.


Perka v. The Queen, [1984] 2 S.C.R. 232 (Can.)