The Fault Element, or Mens Rea
Author | Kent Roach |
Pages | 192-251 |
192
CHAPTER 5
THE FAULT ELEMENT,
OR
MENS REA
Generic references to mens rea are confusing because each dierent
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 such as “purposely,”
“knowingly,” “recklessly,” or “negligently” or specified what particular
fault element applies for each oence.2 As a result, the fault element must
often be inferred by the court s from the legislative definition of each sep-
arate oence. This means that cr iminal oences that may appear at first
reading to have no fault element may actual ly be interpreted as requiring
fault. In some cases, courts will require the proof of fault in relation to
1 R v Tolson (1889), 23 QBD 168 at 185 (CCR) [Tolson].
2 But see Criminal Code, RSC 1985, c C-46, ss 433 and 436 [Code], for clear defin-
itions of separ ate oences of intentional and neglige nt arson.
The Fault Element, or Mens R ea193
all aspects of the prohibited act and in some cases they will not. Refer-
ences in the Criminal Code to c arelessness, dangerousness, or negligence
are misleading bec ause the courts now require proof of a marked depar-
ture from standards of reasonable care in order to distinguish criminal
from civil negligence. The fault element for crimes is often uncerta in and
complex in part because Parliament has long resisted reform proposals
to define fault elements and provide for residual fault rules.
A. CONCEPTUAL CONSIDER ATIONS
In order to explain the fault element of any criminal oence 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 oence; 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 me ns rea for murder requires at least
subjective knowledge that the victim would likely die. Sim ilarly, stati ng
that the me ns rea of manslaughter is objective tell s only part of the story.
The fault is objective foreseeability of bodily harm. The degree of negli-
gence should also be explained, as should the identit y of the reasonable
person used to apply the objective fault or negligence standard.
It is also important to understand the dierences between constitu-
tional requirements and common law pre sumptions 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 establish-
ing 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,
Typically, 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 volunta ry act — intention to cause deat h, or reck-
less and wilfully blind persistence in conduct which one knows is
likely to cause death.3
discus sed below at note 5.
CRIMIN AL LAW194
On this principle, a person is not guilty of assaulting a peace ocer in
the execution of their duties unless the accused has the mens rea for
assault and subjective knowledge that the person is a peace ocer. Sim-
ilarly, the Court classified the old oence 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 trad-
itionally aimed at symmetry between the mens rea and the prohibited
consequence of the oence,” as discussed above. Nevertheless, a major-
ity in R v Creighton concluded:
It is important to distinguish between criminal law theory, which
seeks the idea l of absolute symmetry between t he actus reus and mens
rea and the const itutional requirements of the Charter . . . .
I know of no authority for the proposition that the mens rea of
an oence 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 sucient 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. Oences that do not require
a fault element in relation to all aspects of the actus reus are sometimes
called oences of partial intent, constructive crimes, or crimes based
on predicate oences. The Supreme Court has indicated that requir-
ing fault elements for every element of an oence “would bring a large
number of oences into question” including impaired driving causing
death and sexual assault causing bodily harm. It has ruled that it is
generally acceptable “to distingui sh between criminal respon sibility for
4 R v Hess, [1990] 2 SCR 906.
5 Above note 3 at 378–79. In R v DeSousa, [1992] 2 SCR 94 4 at 966 [DeSousa], the
Court noted that a nu mber of oences punish a person more se verely because
of the consequence s of their actions even though the re is no fault requirement
with regard to t hose aggravating con sequences. Examples cited i ncluded
manslaughte r (s. 222(5)), criminal negligence c ausing bodily har m (s. 221),
crimin al negligence causing deat h (s. 220), dangerous oper ation causing bod-
ily harm (s. 249(3)), dan gerous operation causing deat h (s. 249(4)), impai red
drivin g causing bodily har m (s. 255(2)), impai red driving causi ng death (s.
255(3)), assault causi ng bodily harm (s. 267(1)(b)), aggravated assau lt (s. 268),
sexual a ssault causing bodily h arm (s. 272(c)), aggravated sexual a ssault (s.
273), mi schief causing danger to l ife (s. 430(2)), and arson causing bodil y
harm (s. 433(b)). As noted b y Professor Colvin, “[i]t would, however, be an
error to suppose t hat actus reus and me ns rea always match in t his neat way.”
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