What Are the Two Elements that Make Up Criminal Law in England?

By September 22, 2023 Criminal Law
Understanding Criminal Law in England

In England, criminal law is a complex framework that seeks to establish and enforce the rules and regulations governing unlawful conduct.

According to English law, an action can only be considered a crime if two elements are present: actus reus and mens rea. Moreover, the defendant or suspect needs to manifest a behavioural or physical antisocial state of mind.

In this article, we will answer the question “Which two elements make up criminal law in England?”

Understanding these elements is crucial to grasping the principles underlying criminal liability within the English legal system.

Actus Reus: The “Guilty Act”

Actus reus is the Latin term for “guilty act”, or simply the physical act of committing a crime. It involves actions, conduct or behaviour that constitutes a criminal offence. The actus reus component of a crime is fundamental in establishing criminal liability and must be present for an offence to occur. It may be seen as the use of unlawful and unreasonable force to commit an act. Omission or failure to act can also be considered sufficient for this element.

Types of actus reus

Actus reus itself can be divided into four categories, namely:

Conduct crimes

Conduct crimes involve the unlawful actions or behaviours of an individual, such as physically assaulting someone or stealing property. These crimes focus on the defendant’s specific actions and require proof of the prohibited conduct.

Result crimes

Result crimes require proof of a specific outcome or consequence resulting from an individual’s actions, such as causing death or injury through reckless driving. In these cases, the actus reus is not just the conduct itself but also the resulting harm or consequence.

State of affairs crimes

State of affairs crimes involve situations where the individual’s mere presence or possession of certain items or circumstances is considered a criminal act, regardless of any specific actions taken. An example is possession of controlled drugs with intent to supply.

Crimes of omission

Crimes of omission occur when a person fails to perform a legal duty or obligation, such as failing to provide necessary care to a dependent child, resulting in harm. These crimes are based on the defendant’s failure to act rather than their specific actions.

  1. Offences that can be committed by omission

    Generally speaking, failing to act does not directly constitute a crime under English law. However, there is an exception in certain circumstances.

    As mentioned above, any individual who consciously and voluntarily supervises and protects another may be held accountable if an untoward incident occurs. In the aforementioned circumstance, a babysitter failing to protect their ward from injury or harm may constitute actus reus under the crime of omission.

  1. Defendants who owe a duty to act

    Certain individuals, by virtue of their relationship or occupation, owe a legal duty to act in specific situations. For instance, doctors have a duty to provide medical treatment to patients, parents have a responsibility to care for their children and employers have a duty to maintain a safe working environment.

    Given the fact that the infraction was committed by omission, the prosecutor or complainant carries the burden of proving that the defendant owed a duty to act and, for negligence or some other reason, failed to do so.

Mens Rea: The “Guilty Mind”

Now let us discuss the second crucial element, mens rea. This is the mental aspect of committing a crime. In other words, it is the criminal intent. Here, the culpability of the accused is determined by assessing their state of mind at the time of the offence. Mens rea refers to their mental status; that is to say their intention, knowledge, recklessness or negligence while committing the crime. In simpler words, mens rea is the intent to do harm.

In its lower threshold, an individual may consider an action to be potentially harmful and dangerous, and yet they continue to proceed with their actions. This may be classed as recklessness.

Proving the existence of mens rea is crucial in establishing criminal liability.

Types of mens rea

There are various levels of mens rea, each carrying different degrees of culpability.


This refers to when an individual purposely engages in an act, fully aware of its consequences and intending to bring about the desired outcome. Under English law, intention is further sub-classified into the following:

  1. Purposeful Intention

    Where the defendant wilfully and consciously desires the results of their actions.

  2. Oblique Intention

    Is where it is not the defendant’s aim to bring about a prohibited result, but he foresees that result as virtually certain to occur as a result of his actions.

Knowledge and belief

Knowledge and belief refer to situations where a person is aware of certain circumstances or has a genuine belief that they exist. They can serve as either mitigating or aggravating circumstances. Under current English law, knowledge is defined by true belief, while belief can be considered true or false.

Suspicion and reasonable grounds for belief

Here, an individual will have reasonable grounds to suspect the existence of a fact, even if they are not certain about it. Under existing English law, a certain range of offences can be held to lower standards with regard to an individual’s knowledge of an incident.


As previously defined, recklessness is the foresight that something untoward may result from one’s action. It involves consciously taking an unjustifiable risk, disregarding the potential consequences of such an action.


Negligence refers to the failure to exercise reasonable care, resulting in harm to others. Here, a prosecutor needs to prove to the court that a person in their right mind would not act in the way the defendant did.

Strict liability

Strict liability crimes require no proof of mens rea in relation to one or more aspects of actus reus. An offence has been committed if actus reus is present.


In summary, criminal law in England comprises actus reus and mens rea as its foundational elements. Actus reus refers to the guilty action, encompassing both affirmative actions and failures to act. Meanwhile, mens rea refers to the guilty mind and the mental state and intention of the accused. Together, these two elements form the basis for determining criminal liability and ensuring a fair and just legal system in England.

At Wheldon Law, our team of UK criminal law specialists are committed to helping our clients obtain the best possible outcome for their cases. Please get in touch if you would like some free preliminary advice.