The Role of Mens Rea and Actus Rea in Criminal Law

In the Canadian legal system, there are generally two elements required to prove a crime: the act (actus rea) and the mental state (mens rea). Generally, without proof of these two elements there can be no criminal conviction. However, what may at first seem like a simple equation of two parts, can actually become a very complicated maneuver in the legal field known as criminal law.

The act, or actus rea, must fall in line with a specifically defined offense. Definitions of offenses are taken from the Criminal Code and can include both acts and failures to act. Yet, there is more involved than just reading a few lines from the Criminal Code. If a criminal case goes to trial, a judge will use the definitions in the Criminal Code as well as precedent to determine the outcome of a case. Precedents are previous decisions made by other courts in cases with similar facts. The facts of a case and precedent are often a very important part of a criminal lawyer’s argument, either within a trial setting or simply during negotiations.

Mens Rea is the second key argument for a criminal case. In Latin, Mens Rea means “guilty mind.” Hence, in the Canadian legal system, not only must a person commit an act, they must also have had a specific mental state, or guilty mind, related to the commission of the act. Types of mens rea include intention, knowledge, negligence, recklessness, and willful blindness. Intention and knowledge mean that the person performed an act purposefully, with a desire for the consequences or knowledge that the act will cause the consequence; Recklessness involves consideration that the consequences will possibly occur as a result of the act, but doing the act anyway; Willful blindness occurs when one commits an act while deliberately shutting their eyes to the risks because they do not want to know about the consequences; and Negligence involves a failure to think like a reasonable person given the circumstances. The mental state required to be convicted of a specific crime will likely depend on the act committed. Therefore, mens rea and actus rea almost always need to be partnered together to secure a conviction.

One exception to the mens rea/actus rea partnership is for “strict liability” crimes. If a crime falls within the strict liability category, the person is guilty simply because they committed the act. There are certain circumstances and exceptions which can still be used as defenses in strict liability cases; however mens rea is not one of them.

The Canadian Criminal Legal system is a complicated web of rules and facts that can be difficult to muddle through on your own. If you need assistance, an experienced criminal lawyer can help you work through your case to understand the mens rea, actus rea, rules, and precedent to effectively fight for your rights.