under age sex and the law

Under age sex and the law

A tricky question about under age sex and the law. My advice on the law but also about what is ethical and how we can learn from our mistakes.

I had a boyfriend who, when we first met, was 15 and I had just turned 18. I know I shouldn’t have gone out with a younger guy but he honestly seemed 18 when I met him, which was at my friends party when I was 17. I didn’t want to do anything sexual until he was 16 but he kept insisting and said none of his other girlfriends were this ‘frigid’. I was worried he would leave me so one time he masturbated me and then I did the same back. I regretted it after and ended things with him. Will I get into trouble for this?

It is against the law to have any kind of sex with a 15 year old and as an 18 year old you would be considered an adult and him a child. However, I think, in these circumstances, you would not get in trouble for this.

I’ll explain the law to you (which is really tricky to understand) but also about the guidelines for prosecutions. I’ve spoken to a solicitor about cases like this (I’ve had a few questions about this lately) so some of the advice about the law is what I learnt from him and also reading the Crown Prosecution Service guidelines. However, this is not legal advice. You could speak to a law centre, or a local solicitor who specialises in criminal law (and sexual offences) to get that.

The law and prosecutions

In the UK it’s against the law to have sex with anyone under the age of 16 and this is true even if the offender is also under 16 (but over 10). For young people who are under the age of 18 there are special considerations about whether it’s in the public interest to prosecute someone. 

Prosecutions of incidents like this tend to happen when some harm has been caused. Where there is:

  • abuse, 
  • no consent, 
  • where the younger person has got upset (or a parent has got upset)
  • there is a big difference in physical or emotional maturity
  • if one person is exerting power over the other person
  • if there’s (what some people call) ‘full’ sex and it was the older person ‘doing’ it.

I think in practice, a lot of these would probably apply to you too, even though you were 18. The Police don’t prosecute all potential crimes and they have a lot of discretion. So for these reasons, I don’t think that you are going to be in legal trouble here. 

Just as an FYI, if you did this and didn’t actually know, but just assumed he was over 16 then you could have had a ‘reasonable belief’ defence. However if you knew he was under 16 then that wouldn’t apply. 

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If you were the one who was calling him frigid and making him feel like he had to have sex with you, then I think you would be more likely to be in trouble. However, in this case it was him doing this to you. 

It sounds like this is something he initiated and actually kind of coerced you into. So maybe this was sex that you either didn’t really want to have, or did not consent to. He could have been committing an offence against you — possibly a more serious offence. In cases where offences might have been committed against each other, the Police would more likely investigate the most serious offence. They would then interview who they see as a victim in order to get evidence. More likely, they wouldn’t investigate at all.

Is it right? 

It’s all pretty complicated and as you have pointed out in your question, it gets even more complicated when we think about who did something wrong here. There was coercion on his part, and on your part you could have maybe just said ‘nope’ when you found out he was 15. From your longer email it sounds like things are fine with him.

So what now? Well perhaps you need to find a way to be gentle with yourself about this. Yes you made a mistake, but also it’s a mistake that you were coerced into making. Instead of thinking so much about whether you have broken the law you could start to think about what you learnt about this. 

We all learn how to do sex and relationships from having sex and relationships (as well as from sex ed of course 💅🏻). So it’s okay to use this as a learning experience too. What does it mean to you to have a good ethical relationship with someone? How can you make sure that everything you do is as consensual as possible? 

You might also want to help other people learn from this. How does it affect your views on women, sex and society? What can we learn about the stigma and shame that women get around sex? 

Try my Teach Yourself Sex Ed course (it’s free).

Please leave a (nice) comment below if you like or ask me a question here.

© Justin Hancock, 2024 Find out more about me and BISH here.

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I’ve been a sex and relationships educator since 1999 (with a background in youth and community work). In that time I’ve taught and given advice about sex and relationships with thousands of young people in person and millions online. I’ve worked with many charities, local governments, schools and youth organisations facilitating training and workshops. My two books, Enjoy Sex (How, When, and If You Want To) and Can We Talk About Consent? are widely available around the world. I’ve been on the telly and the radio and have written articles for newspapers and magazines. I’m also a member of the World Association for Sexual Health. Read more about me and BISH here. Find out about my other work here Justin Hancock

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