Common Law Defences

• Author: Karen Jokinen/Peter Keen
• Pages: 449-465

449

Common

Law Defences

22

I. Introduction ............................................. 450

II. Necessity ............................................... 450

A. The Three Elements ................................. 451

B. A Modied Objective Test ............................. 452

C. Onus of Proof ...................................... 452

D. Examples in Driving Cases ............................ 453

E. A Final Word on Necessity ............................ 456

III. Voluntary Intoxication ..................................... 456

A. Voluntary Intoxication and Failure or Refuse to

Provide Oences .................................... 456

IV. Involuntary Intoxication: No Mens Rea ........................ 457

A. Mens Rea and Rebuttable Presumption ................. 458

B. Involuntary Intoxication Scenarios ...................... 459

C. A Final Word on Involuntary Intoxication ................. 461

V. Involuntary Act Due to Automatism . . . . . . . . . . . . . . . . . . . . . . . . . . 462

A. Burden of Proof ..................................... 462

B. The Steps .......................................... 463

C. Dangers in Advancing the Defence ..................... 464

D. Considerations for Defence Counsel .................... 464

VI. Conclusion .............................................. 465

© 2023 Emond Montgomery Publications. All Rights Reserved.

450 Impaired Driving and Other Criminal Code Driving Oences

I. Introduction

Drinking and driving practitioners require a solid understanding of criminal law. It is

beyond the scope of this book to examine every rule of evidence or defence that might

arise, but four common law defences are raised from time to time. Voluntary intoxica-

tion may be a partial defence to specific intent oences, but the courts have ruled it

is unavailable in drinking-and-driving cases. Three available defences are involuntary

intoxication, necessity, and automatism. This chapter briefly discusses the law relat-

ing to each defence and cites several drinking-and-driving cases where these defences

have been advanced.

The common law defences we will consider are:

1. necessity,

2. voluntary intoxication (not a defence),

3. involuntary intoxication (may be a defence), and

4. automatism (may be both a common law and statutory defence).

Common law defences are preserved by section 8(3) of the Criminal Code,1 which

specifies that:

[e]very rule and principle of the common law that renders any circumstance a justifica-

tion or excuse for an act or a defence to a charge continues in force and applies in respect

of proceedings for an oence under this Act or any other Act of Parliament except in so

far as they are altered by or are inconsistent with this Act or any other Act of Parliament.

II. Necessity

Necessity is a common law defence that negates voluntariness. It is, strictly speak-

ing, an excuse rather than an actual defence. It involves an argument that a criminal

act should be excused because it was performed to avoid some other harm. It is now

generally accepted that the criminal act, while wrong, is excused because the person

had no other viable or reasonable choice available.2 This defence is restricted to those

rare cases in which true “involuntariness” is present because the accused had no real

choice.3 Necessity is most commonly advanced in drinking-and-driving cases where

the accused was fleeing a dangerous situation or rushing someone who needs immedi-

ate medical attention to hospital.

1 RSC 1985, c C-46.

2 Perka v The Queen, [1984] 2 SCR 232, 1984 CanLII 23; R v Latimer, 2001 SCC 1.

3 R v Latimer, ibid at para 27.

© 2023 Emond Montgomery Publications. All Rights Reserved.