The Fault Element, or Mens Rea

• Author: Kent Roach
• Profession: Faculty of Law and Centre of Criminology.University of Toronto
• Pages: 169-218

169

CHAPTER 5

THE FAULT ELEMENT,

OR

MENS REA

Generic references to mens rea are confusing because each different

crime has a specif‌ic fault element that must be related to the actus reus

of the specif‌ic crime. In 1889 Stephen J. indicated that mens rea exists

only in relation to particular def‌initions of crime, so that,

“Mens rea” means in the case of murder, malice aforethought; in the

case of theft, an intention to steal; in the case of rape, an intention

to have forcible connection with a woman without her consent; and

in the case of receiv ing stolen goods, knowledge that the goods were

stolen. In some cases it denote s mere inattention. For instance, in the

case of man slaughter by negligence it may mean forgetting to notice a

signal. It appear s confusing to call so many d issimilar states of mi nd

by one name.1

In Canada, confusion about mens rea continues because Parliament has not

clearly and consistently def‌ined fault elements s uch as “purposely,” “know-

ingly,” “recklessly,” or “negligently” or specif‌ied what particular fault

element applies for each offence.2 As a result, the fault element must

often be inferred by the courts from the legislative def‌inition of each

separate offence. This means that criminal offences that may appear

at f‌irst reading to have no fault element may actually be interpreted as

1 R. v. Tolson (1889), 23 Q.B.D. 168 at 185 (C.C.R.) [Tolson].

2 But see Criminal Code, R.S.C. 1985, c. C-46, ss . 433 and 436 [Code], for clear

def‌initions of se parate offences of intentiona l and negligent arson.

CRIMIN AL LAW170

requiring fault. In some cases, courts will require the proof of fault in

relation to all aspects of the prohibited act and in some cases they will

not. References in the Criminal Code to carelessness, dangerousness,

or negligence are misleading because the courts now require proof of

a marked departure from standards of reasonable care in order to dis-

tinguish criminal from civil negligence. The fault element for crimes

is often uncertain and complex in part because Parliament has long

resisted reform proposals to def‌ine fault elements and provide for re-

sidual fault rules.

A.CONCEPTUAL CONSIDERATIONS

In order to explain the fault element of any criminal offence accurately,

it is necessary to specify (1) the circumstances and consequences to

which the fault element is directed, including its relation to the actus

reus of the offence; and (2) the precise fault element required. It is not

very helpful to say the mens rea for murder is subjective. A more pre-

cise approach would be to say the mens rea for murder requires at least

subjective knowledge that the victim would die. Similarly, stating that

the mens rea of manslaughter is objective tells only part of the story.

The fault is objective foreseeability of bodily harm. The degree of negli-

gence should also be explained, as should who is t he reas onable person

used to apply the objective fault or negligence standard.

It is also important to understand the differences between consti-

tutional requirements and common law presumptions of particular

forms of mens rea and how the so-called defences of intoxication and

mistake of fact are really conditions that prevent the prosecutor from

establishing the fault element beyond a reasonable doubt.

1) The Relation of the Fault Element to the Prohibited Act

The fault element does not exist in the air or in the abstract but must

be related to certain consequences or circumstances. As McLachlin J.

has stated,

Typ ica lly, mens rea is concerned with the consequences of the pro-

hibited actus reus. Thus, in the crimes of homicide, we speak of the

consequences of the voluntary act — intention to cause death, or

The Fault Element, or Mens R ea171

reckless and wilfully blind persistence in conduct which one knows

is likely to cause death.3

On this principle, a person is not guilty of assaulting a peace off‌icer in

the execution of his or her duties unless the accused has the mens rea

for assault and subjective knowledge that the person is a peace off‌i-

cer. Similarly, the Court classif‌ied the old offence of statutory rape as

absolute liability because Parliament had excluded fault in relation to

a crucial aspect of the actus reus, namely, the age of the girl.4 The fault

element should generally extend to all the elements of the prohibited act.

The Supreme Court has recognized that the criminal law “has tra-

ditionally aimed at symmetry between the mens rea and the prohibited

consequence of the offence” as discussed above. Nevertheless, a major-

ity in Creighton concluded:

It is important to distinguish between criminal law theory, which

seeks the ideal of absolute symmetry between the actus reus and

mens rea and the constitutional requirements of the Charter . . . .

I know of no authority for the proposition that the mens rea of

an offence must always attach to the precise consequence which is

prohibited as a matter of const itutional necessity.5

In the result, McLachlin J. held that objective foresight of the risk of

bodily harm was a suff‌icient fault element for the crime of unlawful

act manslaughter, even though the actus reus of the crime was causing

death as opposed to causing bodily harm. Offences that do not require

a fault element in relation to all aspects of the actus reus are sometimes

3 R. v. Théroux (1993), 79 C.C.C. (3d) 449 at 458 (S.C.C.) [Théroux]. This is not an

absolute rule, as s een in her own majority judgment i n R. v. Creighton (1993), 83

C.C.C. (3d) 346 (S.C.C.) [Creighton] and discus sed below at note 5.

4 R. v. Hess (1990), 59 C.C.C. (3d) 161 (S.C.C.), discus sed in Chapters 2 and 6.

5 Above note 3 at 378–79. In R. v. DeSousa (1992), 76 C.C.C. (3d) 124 at 141

(S.C.C .) [DeSousa], the Court noted a numb er of offences punish a person more

severely becau se of the consequences of his or her ac tions even though there is

no fault requireme nt with regards to those ag gravating consequence s. Examples

cited included “ma nslaughter (s. 222(5)), crimina l negligence causing bodi ly

harm (s. 221), criminal negl igence causing death (s. 220), dangerous operation

causing bod ily harm (s. 249(3)), dangerous operat ion causing death (s. 249(4)),

impaired driving causing bodily harm (s. 255(2)), impaired driving causing

death (s. 255(3)), assault caus ing bodily harm (s. 267(1)(b)), aggravated ass ault

(s. 268), sexual assault cau sing bodily harm (s. 272(c)), aggrav ated sexual

assault (s. 273), mischief causin g danger to life (s. 430(2)), and arson causin g

bodily har m (s. 433(b)). As noted by Professor Colvin, “[i]t would, however, be

an error to suppos e that actus reus and me ns rea always match i n this neat way.”