Our clients frequently come to us with a similar conundrum – what happens if a crime is committed unintentionally? Is a lack of intent a defence to a criminal offence? Many clients wonder why they are in trouble with the law for something that happened accidentally.

Criminal intent is relevant to some crimes, but not others. It depends on what category the crime falls into. Criminal offences are generally characterised in one of three ways:

  • Strict Liability Offences—the intent of the accused does not need to be proven to establish guilt, but the defence of reasonable mistake is available;
  • Absolute Liability Offences—the intent of the accused does not need to be proven to establish guilt, and the defence of reasonable mistake is not available; and
  • Mens Rea Offences—the prosecution must prove a physical element (actus reus) and a mental element (mens rea) of the offence

Because the relevance of the accused's intent varies crime to crime, we have set out different case examples below.

When intent does not matter – strict and absolute liability

You can be found guilty of some crimes even if you didn't intend to break the law. An example of one of these offences is speeding in a car. Speeding falls into a category of strict liability offences. For strict liability matters, the police prosecutor doesn't need to prove that you intended to speed. They simply need to prove that you were speeding.

Strict and absolute liability offences are commonly found in the Road Safety Act. The reason why the public is held to be strictly liable for these offences is because the government wants to maximise compliance with the law and deter the accused and potential offenders from offending in the future.

While a lack of intent is not a defence in strict liability matters, you may be able to rely on a different defence. The defence of honest and reasonable mistake of fact is available in strict liability matters if the accused held a reasonable belief in a set of circumstances. Let's turn to the example of the offence of driving whilst authorisation suspended. If the accused is caught driving on a suspended licence, they may be able to rely on the defence of honest and reasonable mistake of fact if, for example, they did not know that they were suspended from driving because they did not receive a letter notifying them of this from VicRoads despite the accused providing their correct address to VicRoads. The Magistrate who hears the matter will decide whether the accused's belief in a set of circumstances was truly reasonable based on the unique circumstances of their case.

When intent does matter – mens rea offences

In other offences, the police prosecutor must prove that the client intended to commit the offence. For example, it is an offence to steal. The police prosecutor needs to show that the accused person did the following:

  1. The accused appropriated property belonging to another;
  2. The accused did so with the intention of permanently depriving the other of the property; and
  3. The accused acted dishonestly.

Here we can see that the client's intention is an element of the theft charge. It is the job of the police prosecutor to prove that the accused intended to steal. If the accused can show there was a lack of intent to steal the property, then the prosecution will struggle to prove the charge. Establishing a lack of intent is not always a watertight defence, but it can weaken the prosecution case against you.

How can you prove intent?

Proving another person's state of mind isn't straight forward. However, the landmark Australian judgment of He Kaw Teh v The Queen helps to clarify the rule.

He Kaw Teh v The Queen

The accused in this case travelled by air from Kuala Lumpur to Melbourne. When he arrived at the Melbourne Airport, his baggage was inspected, and he was found to be in possession of a bag which contained heroin beneath a false bottom. The accused claimed no knowledge of the drugs in his bag.

The accused was charged with the importation of prohibited drugs. He lost at trial and was sentenced to life imprisonment.

When this matter was appealed, the High Court decided that the accused's intention is a factor that needed to be taken into account. They asked the question – can it be proven beyond a reasonable doubt that the accused intended to import the heroin? The prosecution weren't able to establish beyond a reasonable doubt that the accused knew about the drugs in his bag and therefore it couldn't be proven that he intended to import the drugs. The accused was found to be not guilty.

We see in this matter that an accused's criminal intent – or lack of intent – can be vitally important to criminal proceedings.

So does intent matter or not?

From looking at different offences, we can see that sometimes the intent of the accused is relevant and sometimes it is not. For most offences, the prosecution must prove that the accused person intended to commit the criminal conduct. However, under strict liability or absolute liability offences, the accused can be found guilty of an offence regardless of whether they intended the criminal conduct or not.