Should Incest be Decriminalised? (Part One)

Image from Game of Thrones (HBO/G.RR. Martin), which depicts an
incestuous relationship between twins Jaime and Cersei

I’m usually pretty open to discussing anything, but even I feel a little uneasy talking about this particular topic. Incest is such a pervasive moral taboo that to even think about it tends to set off emotional alarm bells. Nevertheless, I think there is a serious moral issue to deal here and over the next few posts I want look at it.

The moral issue is this: Should incestuous acts and practices be the subject of criminal sanction? In other words, should those who participate in (consenting) incestuous relationships be incarcerated or otherwise punished? One might think this is a moral issue that has already been resolved to everyone’s satisfaction. Most countries have some kind of law prohibiting incest. For example, in England and Wales, s. 64 of the Sexual Offences Act 2003 makes it an offence for a person to engage in penetrative sexual acts with a certain set of blood relatives. The offence is punishable by up to 2 years in jail.

But a general (legislative) consensus in favour of criminalisation is not enough. Historically, many practices were subject to similar legislative consensuses but unjustly so. Although the analogy is somewhat unfortunate, an obvious example would be the historical consensus in favour of criminalising homosexual activities, a consensus that has now been overturned. Could the same be true of incest?

Vera Bergelson’s recent article “Vice is Nice but Incest is Best: The Problem of Moral Taboo” looks at this question. It discusses five rationales that are traditionally advanced in favour of criminalising incest and highlights their flaws. It then moves on to discuss the likely effect of decriminalising incest. In this series of posts, I want to walk through Bergelson’s arguments, step by step, offering some commentary along the way.

In this introductory post I will do two things. First, I will define what is meant by incest and decriminalisation. Second, I will look at arguments from religion and tradition that are pro-criminalisation.


1. Incest and Decriminalisation
We need to look at two preliminary issues. The first has to do with the nature of incest. No doubt when most of us think about incest — which is presumably not very often — we have a paradigmatic set of cases in mind. For me, the paradigmatic cases would involve (consensual) sexual relationships between a parent and child or between two siblings. But there are a range of non-paradigmatic cases that are also typically covered by incest laws. For instance, the aforementioned Sexual Offences Act 2003 criminalises sexual acts between uncles/aunts and nieces/nephews, half-brothers and sisters, and adoptive parents and children, as well as parent-child and sibling-sibling acts.

What’s more, many incest offences cover non-sexual acts too, such as marriage. For example, as Bergelson notes, many US states make it a criminal offence to marry a certain class of relatives (though usually not first cousins), even if the marriages are non-sexual in nature.

When it comes to the decriminalisation of incest, I suspect the truly challenging cases are the paradigmatic ones — i.e. the cases of parent-child or sibling-sibling sexual activity — but since the peripheral cases are also typically covered by incest prohibitions they need to be considered too. Thus, throughout the remainder of this series, the various pro-criminalisation arguments will be assessed with the paradigmatic and non-paradigmatic cases in mind.

This brings us to a second preliminary issue. What is meant by the terms “criminalisation” and “decriminalisation”. I would define these terms as follows:

Criminalisation: An action or set of actions is criminalised iff a person who culpably engages in those acts can be lawfully subjected to a criminal punishment.

Decriminalisation: An action or set of actions is decriminalised if a person is free to engage in those acts without opening themselves up to the possibility of being criminally punished.

This might seem like very basic stuff, but it’s important. The definition of decriminalisation that has just been offered is a narrow one. It is saying that a call for decriminalisation is simply a call for the removal of criminal sanction and nothing more. It is not, for instance, a call for the support or encouragement of the acts in question. In other words, the definition is pointing out that it is possible to think that an act ought to be decriminalised without thereby being forced to think that the act is, all things considered, good. This possibility must be kept in mind when considering the, basically pro-decriminalisation, position that is set out in Bergelson’s article.

That said, it might be open to the defender of incest laws to argue that the distinction between decriminalisation and full-blooded endorsement is flawed. It could be that once we remove the criminal sanction on incest we run into either a logical or causal slippery slope. For example, if we decriminalise incestuous marriages, is it not the case that we are thereby obliged to afford such marriages the same legal rights and protections as all marriages? And since those rights and protections are designed to encourage marriage, does it not follow that we thereby start to encourage incestuous marriages? Responding to such slippery slope concerns will be necessary if the pro-decriminalisation position is to succeed.

Anyway, enough of this. Let’s move on to consider some pro-criminalisation arguments.


2. Arguments from Religion and Universal Tradition
The first pro-criminalisation argument discussed by Bergelson is really two separate arguments: (i) the argument from religious authority; and (ii) the argument from universal tradition. As one might imagine from the titles, neither has a great prospect of success, but let’s consider them anyway.

The argument from religious authority holds that the criminalisation of incest can be justified by appeal to some religious authority. Most often, this will consist in an appeal to some authoritative religious text such as the Hebrew Bible, New Testament or Koran. This leads to the following argument:

• (1) If a practice is prohibited by some religious text or authority, then it ought to be criminalised. 

• (2) Incest is prohibited by religious texts and authorities. 

• (3) Therefore, incest ought to be criminalised.

Obviously, for someone of my beliefs and inclinations, the principle articulated in premise (1) of this argument has no merit. As a non-believer I do not recognise such authorities nor think they should have an impact on the secular legal system. But even believers should be wary of this principle. For starters, if they accept the principle of church-state separation then, arguably, accepting that religious authority can determine secular laws in this manner undermines this principle. Furthermore, most believers have an inconsistent attitude to religious authorities. The Bible prohibits a great many things, for instance the eating of pork, but very few people, including those who accept that prohibition, think that the eating of pork merits criminalisation. Biblical authority alone won’t get you to criminalisation. An additional principle is needed for that.

Leaving that to one side, there are concerns about premise (2) as well. As Bergelson notes, some religious groups seem to allow forms of non-paradigmatic incest. For example, Judaism permits uncle-niece or aunt-nephew marriages in certain instances (I’m assuming this is true). Indeed, some legislatures (the example of Rhode Island is given) historically granted Jews an exemption from the prohibition against this type of incest for these reasons. In addition to this, if one takes some biblical stories at face value (e.g. Adam and Eve, Noah and the Flood), then it seems like incest must be permissible in some instances. So, once again, it’s not necessarily true that incest is prohibited by religious texts and authorities.

So much for the argument from religious authority. What about the argument from universal tradition? This argument suggests that incest ought to be criminalised because there is a universal tradition in favour of this view. In other words:

• (4) If a practice has been prohibited by every society in human history, then it ought to be criminalised. 

• (5) Incest has been prohibited by every society in human history. 

• (6) Therefore, incest ought to be criminalised.

We’ve already seen that premise (2) is false, at least in cases of non-paradigmatic incest. And Robin Fox’s 1980 book on incest across human history (The Red Lamp of Incest) claimed that there had been at least 96 human societies that allowed some form of incest, including two societies that permitted the paradigmatic form. Still, it is true that the vast majority of human societies have been against it, so one could imagine a revised version of premise (1) that only claimed authority from the near-universal prohibition of incest.

But that just turns the critical spotlight on premise (1), which, even in the revised form, seems deeply inadequate. Why does human tradition have any moral weight on this matter? The vast majority of human societies have prohibited other things (e.g. homosexuality and female suffrage) that we no longer think ought to be criminalised. Indeed, laws on incest seem to be following suit, with an increasing number of countries decriminalising the practice (Bergelson mentions several in her article). There is more to be said the moral weight of human tradition, some of which was said in a previous post I wrote, but what has been said seems sufficient to dismiss this particular argument.

In sum, neither the argument from religious authority nor the argument from universal tradition succeeds. What they may help with, however, is explaining some of the historical basis to the prohibition on incest. Although, even here, there is some reason to be suspicious since evolutionary explanations are often deemed superior to religious or cultural ones on this particular topic. I won’t have time discuss such historical and evolutionary explanations, or the interactions between them, in this series, but suffice to say there is a rich (and sometimes rewarding) literature on the topic.

I’ll leave it there for now. In the next post, we’ll discuss two more arguments for the criminalisation of incest. The first being the argument from genetic defectiveness, which is probably the most popular secular pro-criminalisation argument. The second being the argument from protecting the family unit. Stay tuned.