Honest and Reasonable Mistake About Age in Child Sex Cases

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Imagine this: You’re 17 or 18 years old and go out one night to a party with some friends, where you meet a person who says they are 16. You start chatting to them, one thing leads to another and you end up engaging in consensual sexual activity.

The next day, the police come knocking at your door and charge you with having sexual intercourse with a minor. It turns out that the person you had sex with was lying about their age, and is under 16, which is the age of consent in NSW.

In these circumstances, can you be convicted of a child sex offence? Or are you able to argue that you honestly thought that they were over the age of 16?

Whether you can avoid a conviction because you made an honest and reasonable mistake is a common question for criminal defence lawyers to be asked.

Such a defence can be raised in a multitude of situations to absolve a defendant of guilt – for instance, in larceny (stealing) offences, many driving offences, and fraud offences.

Here we help you understand the ‘honest and reasonable mistake’ defence and how it applies in child sex offences.

Understanding the Law

Firstly, it’s important to remember that technically, an assertion that a defendant made an ‘honest and reasonable mistake’ is not a defence.

In legal jargon, it’s called a ‘common law ground of exculpation of honest and reasonable mistake of fact.’ However, for convenience sake, we will call it a defence in this blog.

So how does this work?

To raise this argument, the defendant must put forth evidence that they had an honest and reasonable belief ‘in a state of affairs such that, if the belief were correct, the conduct of the accused would be innocent.’ That evidence must be more than a mere ‘ignorance of the law.’

If a defendant wants to argue that they made an honest and reasonable mistake, evidence of that ‘defence’ can be raised at any time during the trial. The onus will then shift to the prosecution to prove beyond a reasonable doubt that the defendant did not make an honest and reasonable mistake.

However, experienced criminal lawyers will generally try to ascertain whether the ‘defence’ exists before the trial, and will write to the prosecution explaining the scope of the mistake and requesting that the charges be dropped on that basis.

Often, this spares clients the cost, stress and time of a defended hearing or trial.

Honest and Reasonable Mistakes and Child Sex Offences

To understand how the defence can be raised in cases concerning child sex offences, it is necessary to consider recent case law.

The High Court case of CTM v The Queen [2008] concerned the case of a 17-year-old man charged with sexually assaulting a minor.

The girl, who was aged 15 at the time, had been out drinking and returned to CTM’s unit, where she continued drinking with him and his friends. She was taken to a bedroom and allegedly sexually assaulted by CTM and two of his friends.

In cases concerning children under the age of 16, the fact that they gave consent to the sexual activity is neither a defence nor a mitigating factor. This is because the approach taken by the law is that ‘children are to be protected from sexual conduct, even if they are willing participants.’

CTM was therefore charged with the offence of sexual intercourse without consent.

In the District Court, he was found ‘not guilty’ of this charge, but guilty of the offence of ‘sexual intercourse with a person aged between 14 and 16.’

CTM argued that he had made an honest and reasonable mistake as to the complainant’s age, as she had told him that she was 16, and he believed that she was in year 10.

It was a particularly difficult case as Parliament had recently reformed the law in relation to sexual offences concerning minors.

Prior to 2003, the Crimes Act provided a specific defence in section 66C where the accused person reasonably believed that the complainant was over the age of 16 and had consented to the sexual activity.

But after the Act was reformed in 2003, there was no explicit defence in the section.

The High Court found that in these types of cases, an accused person was able to raise evidence of honest and reasonable mistake, but in this case CTM had not raised evidence to establish that he was honestly mistaken as to the complainant’s age.

The case made it clear that the defence must raise some evidence of an honest and reasonable mistake during the course of the trial in order for the onus to then shift to the prosecution.

The defence failed to do this in CTM’s case because, although he had stated in a police interview that the complainant had told him she was 16, this matter was not explored in cross-examination – which could be seen as a grave strategic mistake by the defence lawyers.

Honest and Reasonable Mistake in Child Pornography Cases

While an honest and reasonable mistake defence can be raised in sexual assault cases concerning children, the situation is slightly different when it comes to child pornography cases – or ‘child abuse material’ cases as they are now called.

This is because, under section 91FB of the Crimes Act, ‘child abuse material’ refers to material which depicts ‘a person who is, appears to be or is implied to be a child’ as a victim of torture, cruelty, or physical abuse, or who is engaged in a sexual pose or activity, or their private parts.

This means that you could technically be convicted of a child pornography offence even if the subject of the material was actually over the age of 18 – so long as they reasonably appear to be a child.

A person can also be found guilty where the material in question has been altered to make the subject appear more child-like.

In determining whether a person is guilty, the court will consider whether a reasonable person would regard the material as being offensive.

This means that the court will take into account matters such as the standards of morality, decency and propriety generally accepted by reasonable adults and the literary, artistic, educational or journalistic merit of the material.

At the end of the day, it’s better to be safe than sorry in these types of cases and steer clear of any material which may depict an underage person.

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Ugur Nedim

Ugur Nedim

Ugur Nedim is an Accredited Criminal Law Specialist with 25 years of experience as a Criminal Defence Lawyer. He is the Principal of Sydney Criminal Lawyers®.

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