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Autonomy and morality: What are the limits of the law?

What are the limits of the law? Dr Hrafn Asgeirsson discusses autonomy and morality and how they link to this question.
So in R v BM, the criminal case, it raises a host of questions. But in general, the master questions is that it prompts us to consider the proper scope of the criminal law. And the way in which it does this is that our jurisdiction, in particular, prides itself of respecting individual autonomy and freedom. We hear this a lot not just in political discourse, but also in individual judicial decisions. So we see the law priding itself of respecting individual autonomy, and we see that in various case history in various cases across criminal law, tort law, in a variety of contexts. So we know it’s a fundamental core value of not just our political system, but our particular jurisdiction.
So individual autonomy, one of the things that autonomy is supposed to be able to do is to make us able to consent to things and we consent to things all the time. We consent to undergoing operations, so that the injury inflicted upon us is not wrongful. Right, so the idea is that we should be protected against wrongful infliction of harm. But there are cases where our ability to consent negates the wrongfulness, and for example the context of medical procedures is one such. And the question then arises in case of body modification, not just piercings and tattoos on the such, but the more extreme kind in which Brenda McCarthy was involved, why should the law not respect that as well?
And it’s the burden of the law to answer that question. And it’s for us to decide, in this first half of the first part of this week. To try to figure out, tentatively, given what we’ve read and the space that we have to think about this. Do we think the law has provided good reasons for not respecting the ability of the recipients to consent to the kind of harm inflicted on them in this context?

Now that you have heard about the R v BM [2018] case and formed your own impression of it, we can examine one of the core issues that it raises. We will focus on the pressure the case puts on the law’s commitment to the value of autonomy – that is our capacity for reasoning and independent action, including also our capacity to exert control over our affairs, such as by making promises and giving consent.

The value of autonomy

Liberal democratic societies generally put a high premium on the autonomy of the individual, and its value is embedded in the law in various ways. In the UK, for example, it embedded in many aspects of legislation, from the way people think about the role of constitutional law to particular judgements in important tort cases.

When should the law interfere?

Many think that the law should interfere with our autonomy only if it’s necessary to protect others from wrongful harm. However, the power of consent is to make permissible things that would otherwise be wrongful – in the context of bodily harm, this applies, for example, to surgery, tattooing/piercing, and boxing. There is a good case, therefore, to be made that by consenting to the respective body modifications, Brendan McCarthy’s customers made the harm he inflicted morally permissible. But if that’s the case, and if the law should interfere with our autonomy only to protect people from wrongful harm, then it seems like the courts overstepped the proper limits of the law. That’s a big ‘if’, however, and people have tried to justify in various ways the courts’ reluctance to accept consent in cases involving serious harm.

The role of dignity

Some thinkers, such as Professor Dennis Baker (2012), have argued that if the harm is serious enough (both in degree and with respect to reparability/irreparability), as it may have been in R v BM, then consent does not manage to remove it wrongfulness (as it would do in less serious cases). If that’s correct, then the value of our autonomy sometimes loses out to what we can call our ‘dignity’, which in turn would require us to change our minds a bit regarding what we think the proper limits of the law are.


In the video, what is the ‘big question’ relating to body modification? And how does this relate to the idea of autonomy?
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Baker, D. J. (2012) ‘The moral limits of consent as a defense in the criminal law’, New Crim. L. Rev., 12(1), pp. 93–121. doi: 10.I525/nclr.2009.Iz.s.93.

R v BM [2018] EWCA Crim. 560. Available at: (Accessed 13 December 2021).

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