The Defenses of Mistake of Fact and Mistake of Law in Criminal Cases

There are two types of mistakes that can be made when it comes to criminal cases- mistakes of fact, and mistakes of law.

The two defenses of mistake of fact and mistake of law can be used in criminal cases to argue that the defendant did not have the required intent for the crime. If successful, these defenses can lead to a reduction or dismissal of charges. However, they each have their own requirements and limitations that must be met in order for them to be successful.

Both of these defenses can be used in an effort to have the charges against you reduced or dismissed altogether. In this blog post, we will discuss the differences between these two types of mistakes, and outline how each one can be used as a defense in a criminal case.

Elements of a Crime

In order to be convicted of a crime, the prosecution must prove that you committed all of the elements of that crime. The elements of a crime are the facts that the prosecution must prove in order to convict you.

For example, if you are charged with theft, the prosecution must prove that you took something without the owner’s permission and with the intent to keep it for yourself. If they cannot prove all of these elements, then you cannot be convicted of theft.

There are two elements of a crime; the first is the mental element, and the second is the physical element.

Mens Rea

The mental element is also known as mens rea, and it refers to your state of mind at the time that you committed the crime. For example, if you are charged with murder, the prosecution must prove that you had the intent to kill someone when you committed the act.

Actus Reus

The physical element is also known as actus reus, and it refers to the actual act that you committed. For example, if you are charged with theft, the prosecution must prove that you took something without the owner’s permission.

Affirmative Defences

Affirmative defences are grounds for a criminal defendant to avoid liability, despite the fact that the prosecution has proven all of the elements of the crime.

In some cases, an affirmative defence may completely negate one or more of the essential elements of the crime. In other cases, an affirmative defence may only serve to reduce the defendant’s culpability.

Affirmative defences are technically admissions of guilt, in that the defendant is admitting to committing the actus reus of the crime. However, these defences provide a justification for why the defendant should not be held liable.

The two most common affirmative defences are mistake of fact and mistake of law.

Mistake Of Fact

A mistake of fact is defined as a belief that is not in alignment with reality. This type of mistake can be used as a defense if you can prove that you had a reasonable belief that your actions were not criminal.

For example, if you are charged with theft and you can show that you reasonably believed that the item you took did not belong to anyone, then you may be able to use mistake of fact as a defense. Similarly, if you are charged with assault and can show that you reasonably believed that the person you were attacking was about to harm you, then this may also serve as a valid defense.

What Constitutes a Mistake of Fact as Defence in Criminal Cases

In order for a mistake of fact to be successfully used as a defence, it must meet certain criteria.

First, you must show that you actually held the mistaken belief. This means that simply saying “I didn’t know it was a crime” will not suffice – you must be able to provide evidence that supports your claim.
Second, you must show that your belief was reasonable. This is where things can get tricky, as what one person may deem as reasonable may not be seen as such by the court. Factors that will be taken into consideration include the surrounding circumstances, your level of education and intelligence, and whether or not you had any reason to doubt the legality of your actions.
Third, you must show that your mistake of fact was the reason why you committed the crime. This means that if you would have still committed the crime even if you had known it was illegal, then your defense will likely not be successful.

If you are able to meet all of these criteria, then there is a chance that your charges could be reduced or dismissed altogether. However, it is important to keep in mind that this is not always the case – ultimately, the decision lies with the court.

Mistake of Law

Mistake of law, on the other hand, is when an individual commits a crime without knowing that it is against the law. This type of defense is typically only used in very rare circumstances, and usually only when the individual has made a good faith effort to comply with the law.

An example of this would be if you are charged with a crime that has only recently been made illegal, and you can show that you were not aware of the change in the law.

What Constitutes a Mistake of Law as Defence in Criminal Cases?

The mistake of law defence is a partial defence. This means that if the accused is successful in using the defence, they will not be acquitted of the charge, but the charge will be reduced to a lesser offence.

For the mistake of law defence to be successful, the accused must prove all of the following:

They did not know that their actions were against the law; and
A reasonable person in their position would not have known that their actions were against the law.

The first part of the defence, that the accused did not know that their actions were against the law, is relatively straightforward. The second part, however, can be more difficult to prove.

In order to prove that a reasonable person in the same situation as the accused would not have known that their actions were against the law, it is necessary to show that there was some ambiguity or lack of clarity in the law itself. This can be difficult to do, as courts will often interpret laws narrowly and find that there was no ambiguity or lack of clarity.

It is also important to note that this defence can only be used in cases where the accused has been charged with a criminal offence, and not a regulatory offence. Regulatory offences are those that are created by administrative bodies, such as by-laws or regulations. This defence cannot be used in cases where the accused has been charged with breaking a regulation.

Applicability of The Defence of Mistake

The defence of mistake is available for all offences, except those of strict liability.

An offence of strict liability is one where the actus reus and mens rea are not required to be proved, such as parking offences. This means that the defence can be used for both general intent and specific intent offences.

The defence can also be used in cases where the accused has been charged with an offence that requires proof of fault elements other than intention, such as recklessness or negligence.

However, there are some limits on when the defence can be used.

The first is that the mistake must be a genuine one. This means that it cannot be a deliberate decision to ignore what the law says. For example, if someone is charged with drink driving and they claim that they did not know that the legal limit was 0.08% blood alcohol content, this defence will not be available to them if it can be shown that they deliberately chose to ignore this information.
The second limit is that the mistake must be one that a reasonable person would make in the same situation. This means that if the accused could have easily avoided making the mistake, such as by checking the relevant law beforehand, then the defence will not be available to them.
The third limit is that the mistake must be about the law itself, and not about anything else. For example, if someone is charged with assault and they claim that they did not know that it was against the law to hit someone, this defence will not be available to them if it can be shown that they knew it was against the law to hit someone but did not know that the person they hit was a police officer.
The fourth and final limit is that the mistake must have been made before the commission of the offence. This means that if the accused realises after they have committed an offence that what they did was against the law, they cannot use this defence.

Strict Liability Crimes and the Defences of Mistake of Fact and Mistake of Law

A strict liability crime is a crime that does not require any proof of intent to commit the act. The prosecution needs only to prove that the act was committed, and the accused will be held liable even if he or she did not intend to commit the crime. Generally, these are lesser offences such as traffic violations.

There are many examples of strict liability crimes, but some of the most common include:

Speeding
Driving without a valid license
Not having insurance
Overloading a vehicle beyond the legal weight limit

While these offences are typically only punishable by fines, there are some instances where strict liability can lead to more serious consequences. For example, if someone is caught driving without a license and gets into an accident that injures another person, they could be charged with a felony and face jail time.

The courts have held that a mistake of law is not a defence to a strict liability crime. This means that if an accused commits a crime that does not require proof of mens rea (intention), then they cannot use the defence of mistake of law.

The rationale behind this is that in order for someone to be found guilty of a strict liability offence, the prosecution needs only to prove that they committed the actus reus (the physical act) of the offence. The accused does not need to have had any intention to commit the crime.

However, there are some exceptions to this rule. The courts have held that a mistake of law can be a defence to a strict liability offence in certain circumstances. These include cases where:

The accused reasonably believed that their actions were not illegal;
The mistake was due to an official interpretation of the law; or
The law is ambiguous and the accused made a reasonable mistake in interpreting it.

Other Defences to Criminal Liability

There are a number of other defences to criminal liability that have been developed over time. These include:

Intoxication,
Duress,
Necessity,
Automatism,
Insanity,
Self-defence,
Provocation.

The Defence of Intoxication

Intoxication is a defence that is available in limited circumstances. It can be raised where the accused was so intoxicated at the time of the offence that they did not know what they were doing was wrong. This is known as ‘non-insane automatism’. An example of this would be if someone with no history of violence took drugs and then assaulted someone, without knowing what they were doing.

The intoxication defence can also be raised where the accused was not so intoxicated that they did not know what they were doing was wrong, but their intoxication caused them to act in a way that they would not have otherwise acted. This is known as ‘voluntary intoxication’. An example of this would be if someone who normally behaves peacefully becomes aggressive after drinking alcohol.

However, the intoxication defence is not available in all circumstances. It cannot be raised where the accused was voluntarily intoxicated and the offence they committed was one that required a specific intent.

This means that if someone commits an offence while voluntarily intoxicated, they will not be able to use the intoxication defence unless the element of intention for that offence does not require proof of a specific intent.

An example of this would be if someone who is very drunk breaks into a house with the intention of stealing something. In this case, they would not be able to use the intoxication defence as breaking into a house with the intention of stealing something requires proof of a specific intent.

The courts have also said that the intoxication defence cannot be used where the accused was voluntarily intoxicated and the offence they committed was one that is ‘inherently dangerous’.

This means that if someone commits an offence while voluntarily intoxicated, they will not be able to use the intoxication defence if the offence they committed is one that is considered to be so dangerous that it should never be committed regardless of whether the person intends to do harm or not.

An example of this would be if someone who is very drunk gets behind the wheel of a car and drives. In this case, they would not be able to use the intoxication defence as driving a car is an inherently dangerous act.

The intoxication defence can only be raised in limited circumstances and it is important to get legal advice before using this defence.

The Defence of Duress:

Duress is a defence that can be raised where the accused committed an offence because they were threatened with death or serious injury if they did not commit the offence. This defence can only be used in certain circumstances and it is important to get legal advice before using this defence.

The defence of duress can only be raised where the accused was under threat of death or serious injury at the time of the offence. The threat must have been made against the accused or someone close to them, such as their family. The threat must also have been made by another person and not by the accused themselves.

The defence of duress can also only be used where the accused had no way of escaping from the situation other than by committing the offence. This means that the defence cannot be used where the accused could have easily avoided committing the offence or where they had time to escape from the situation.

The defence of duress can only be used in limited circumstances and it is important to get legal advice before using this defence.

The Defence of Necessity

Necessity is available as a defence to both property offences and violent offences. It can be raised where the accused reasonably believes that their actions were necessary to prevent an imminent and serious evil, and where there are no other means available to avert the evil. The harm caused by the accused must not be disproportionate to the harm avoided. This defence will not be available where the accused could have reasonably foreseen the consequences of their actions.

The leading case on this defence is R v Dudley & Stephens, in which two shipwrecked sailors killed and ate a third sailor in order to survive. The House of Lords held that necessity was not a defence to murder, as it would open up too many potential crimes to this defence. However, the defence has been codified in some jurisdictions, such as Australia.

The Necessity Defence is also sometimes called the “Choice of Evils” Defence.

It is important to note that this is a defence of last resort – it can only be raised where there are no other options available.

This defence will not be available if the accused could have reasonably foreseen the consequences of their actions.

Automatism

Automatism is a state where the accused is not in control of their actions due to an external factor. This could be due to a mental illness, sleepwalking, or shock. If the accused can prove that they were in a state of automatism at the time of the crime, then they can avoid criminal liability.

There are two types of automatism: non-insane and insane.

Non-insane Automatism

Non-insane automatism occurs when the accused is in a normal state of mind but something outside of their control causes them to act involuntarily. An example of this would be if someone was sleepwalking and committed a crime while in that state.

Insane Automatism

Insane automatism occurs when the accused is in a state of mental illness and as a result, commits a crime. An example of this would be if someone with schizophrenia thought that they were being chased by zombies and as a result, killed someone.

In order for the defense of automatism to be successful, the accused must prove that:

They were in a state of automatism at the time of the crime;
The automatism was not self-induced; and
The automatism was not caused by voluntary intoxication.

If the accused can prove these three things, then they can avoid criminal liability. However, if the accused cannot prove these things, then they will be held liable for their actions.

Automatism is a difficult defence to prove because it requires the accused to show that they were not in control of their actions. This can be difficult to do, especially if the accused was intoxicated at the time of the crime. However, if the accused can prove that they were not in control of their actions, then they may be able to avoid criminal liability.

The Defence of Insanity

Based on the M’Naghten Rules – The defence of insanity is based on the principle that a person who is mentally ill should not be held criminally responsible for their actions. The M’Naghten rules, named after the English case in which they were first articulated, set out the test for determining whether a person is insane and therefore not criminally responsible for their actions.

Under the M’Naghten rules, a person is only considered to be insane if they are suffering from a mental illness that means they do not understand what they are doing or that it is wrong.

The defence of insanity is based on the premise that a person cannot be held criminally responsible for their actions if they were not in control of their mental faculties at the time of the offence. This defence is available in very limited circumstances and is often unsuccessful.

To be successful, the accused must prove on a balance of probabilities that they were suffering from a mental illness or disease at the time of the offence which rendered them incapable of understanding that their actions were wrong.

This can be a difficult task as it requires expert evidence to support the claim, and even then juries are often reluctant to find an accused not guilty by reason of insanity.

Self Defence: the Defence of Others and of Property

The legal defence of self-defence allows an accused to use as much force as is reasonably necessary in order to protect themselves or another person from bodily harm. This defence can be raised when the accused is facing charges such as assault, aggravated assault, and manslaughter.

The courts will consider a number of factors when determining whether or not the force used was reasonable, including the perceived threat, the proportionality of the response, and whether there were any other options available.

The same principles apply when an accused is defending their property; however, the courts will also take into account whether the property was worth more than human life. In general, the defence of self-defence or defence of property can only be successful if the accused can prove that they reasonably believed that they or their property were in imminent danger.

The Defence of Provocation

This is a partial defence which may result in a conviction for manslaughter instead of murder. The defence may be raised where the defendant was provoked (that is, there was an act or series of acts by the victim which caused an emotional reaction in the accused) and as a result, the accused lost self-control and killed the victim. In order to successfully raise this defence, the accused must prove that:

He/she was provoked;
A reasonable person would have reacted in the same way; and
As a result of losing self-control, he/she committed homicide.

The test for provocation is whether or not an ordinary person in the position of the accused would have been provoked to lose self-control. The defence is not available if the accused was motivated by revenge, resentment or ill will.

The courts have acknowledged that what may be considered provocation can vary based on an individual’s characteristics. For example, someone with an abusive background may be more likely to react violently to a minor insult than someone who has not experienced abuse.

It is important to note that the defence of provocation is only available where the defendant killed the victim – it cannot be raised where the defendant caused injury short of death.

If you are able to successfully raise the defence of provocation, the sentence for manslaughter will be less than it would be for murder.

Conclusion