Chapter 8:

Defences

What is a defence?A lawful excuse for committing an

offence.• Evidence that you lacked the mens rea or

that you lacked the actus reus (or both):

– Mental disorder– Automatism– Intoxication– Mistake of fact– Duress/compulsion by threats– Consent– Legal duty– Alibi

Alibi

• Evidence that the accused was not present at the scene of the crime.

• Actus Reus and Mens Rea do not exist.

Automatism

• Unconscious involuntary actions• Mens Rea does not exist• Sleepwalking (R v. Parks)• Proof often lies in the (medical) history of

the accused.

Kenneth Parks

Mental Disorder• Formerly called insanity• Mens Rea does not exist.• A ‘disease of the mind’• Proven by psychiatric evaluation• Not able to realize the full consequence of the

crime.• Are not ‘morally blameworthy’• NCR-not criminally responsible: This plea, if

accepted, will result in the accused being held in psychiatric detention rather than prison. Their status will be reviewed regularly.

• Changes made to this area in 1992 included capped sentences proportional to crime.

• Peckham v. Ontario

Intoxication

• Not a defence for violent or sexual offences.

• Mens Rea does not exist.• R v. Daviault – Supreme Court ruled that he

could not form the necessary intent for sexual assault.

• This precedent was voided by new legislation by the federal government in 1995

• Involuntary intoxication is a defence.

Mistake of fact

• Ignorance of the law is not an excuse.

• Mens Rea does not exist.

• However, honest mistaken belief in the circumstance may void the mens rea element.

Self-Defence• Actus Reus and Mens Rea both exist.• However, despite both elements being

proven, the accused had reason to act this way-defending themselves.

• Imminent and real danger. (Clear and present danger)

• Cannot use excessive force; only enough to repel the threat. (subjective)

• R. v. Lavallee

Duress

• ‘Compulsion by threats’• Actus Reus and Mens Rea both exist.• Accused was threatened (real) with

death or bodily harm.• Person making threats must be

present when crime is being committed.

• Not an excuse for serious offences causing physical harm to others or serious offences like arson or robbery.

Consent

• You did, or believed you did, have permission.

• Mens Rea does not exist.

Legal Duty

• Police officers using justified force on the job.

• The force must be reasonable and necessary under the circumstances.

• Searchcan be referred to as an assault [non-consensual application of (gentle)force]

• Mens Rea and Actus Reus both exist.

Entrapment

• Police aid the commission of an offence.

• Abuse of procedure.• Defense must prove (on the balance of

probability) that the investigators abused process.

• Stay of proceedings for one year.

• Actus Reus and Mens Rea both exist.

Double Jeopardy

• Cannot be tried twice for the same offence if you have been convicted and served sentence.

• Not be charged under multiple offences.