(Image by Mediamodifier from Pixabay)

Every now and again, you read something that makes you feel so seen, that leaves you saying ‘Yes, that’s me! And that’s me too! This is all so true!’ A good few years ago, I read this blog post by Scott Alexander and had exactly that experience. The post posits that when it comes to understanding why things can go wrong, some people think it essentially boils down to people making mistakes, while others think it boils down to there being a conflict between different actors who have different interests.

I am a die-hard mistakes theorist. The descriptions of mistakes theorists rang so true for me, but this paragraph in particular always makes me wary of myself:

Mistake theorists love worrying about the complicated and paradoxical effects of social engineering. Did you know that anti-drug programs in school actually increase drug use? Did you know that many studies find raising the minimum wage hurts the poor? Did you know that executing criminals actually costs more money than imprisoning them for life? This is why we can’t trust our intuitions about policy, and we need to have lots of research and debate, and eventually trust what the scientific authorities tell us.

As a mistakes theorist, I’m always drawn to counterintuitive outcomes that subvert your expectations, and I’m especially drawn to the fascinating mechanics that explain why the intuitive outcome turned out to be the opposite of what happened. However, I, and other mistakes theorists, need to be careful – most things in the world do conform to our expectations. Most things follow boring, predictable patterns dominated by first-order effects. One example, which should be obvious and yet seems to have many people arguing the opposite is that – abortion bans do lower the abortion rate.

We’ve blogged about this before, as have others. Secular ProLife has a fantastic summary of the evidence to date – as the impact of Dobbs beds in, expect more studies comparing different States with different abortion laws. But, why is this fact so surprising? Why do so many insist that abortion bans make no impact on the number of abortions, but merely on where the abortion takes place (either in another country versus this country, or in an unsafe setting versus a safe(r) setting within the same country)? This insistence played a role in changing many minds on the issue of abortion, including Simon Coveney, then Tánaiste of Ireland.

This line of thinking, that people will have just as many abortions, just in different countries or settings, is one example of what some Bright Spark on Twitter/X has decided to dub ‘The Determined Actor Fallacy’:

In other words, the idea is that because a ban is not 100% foolproof, it is therefore useless, because there will always be someone somewhere who gets around the ban. This is only a good argument if the aim of the ban was to stop absolutely every single instance of whatever we were banning. However, if the aim of the ban is to reduce whatever it is we’re banning, maybe even reduce it by a lot, then the Determined Actor Fallacy is, indeed, a fallacy.

There are so many examples. Prohibition didn’t end all alcohol consumption, because some Determined Actors continued to consume alcohol illegally – but it did reduce it enough to have a clear and noticeable impact on diagnoses of cirrhosis of the liver. Reducing the carbon monoxide content of town gas in Britain didn’t end all suicides – but it did all but eliminate suicide using a gas oven, without a shift to use of other methods. Those who would have committed suicide using a gas oven turned out, thankfully, to be not Determined Actors. People respond to incentives, and first order effects tend to dominate over counterintuitive ones.

If you’re having a conversation with someone who seems convinced that abortion bans don’t work because people will have abortions anyway, it’s worth introducing them to the idea of the Determined Actor Fallacy. It’s worth giving the examples mentioned above of how even a small change in how convenient (as opposed to how possible) something is can have a material impact on behaviour. And it’s also worth discussing whether laws that prohibit anything from murder to parking in loading bays do anything to reduce the instances of such behaviours – even if some Determined Actors will nonetheless commit murder, or park in a loading bay (or both).

It’s important to note, though, that bans are not a long-run solution. Abortion bans should not be the end goal of the pro-life movement, but should rather be seen as a means to an end. This is, in fact, partly true because of actual Determined Actors – but we’ll discuss that in a future post.

Muireann