Note: This post was crossposted from the Lauren Policy blog by the Forum team, with the author's permission. The author may not see or respond to comments on this post.

When I wrote a post about immigration and crime in the US, I promised a followup with other countries. A mere four months later, here it is.

An important caveat to start: the evidence for each individual country is much scarcer here. The US has 350 million people and 16,000 economists;^[1] the UK has fewer than 70 million people and maybe a couple thousand economists. This scales accordingly with other countries; my conclusions for each country are therefore much weaker. Still, I’ll make a stab at summarizing what we do know.

Several caveats upfront: I only speak and read English. This restricts the amount of information I have on some countries. I also focus here, as I have in other posts, on the academic causal evidence. Much of the reporting on immigration and crime examines the correlation between immigration and crime. That is interesting enough, but I want to know if immigration causes crime.

The UK

In my last post, I included this chart:

(from Marie and Pinotti 2024, though the FT also has a variant on this chart)

In this chart, you can see an Anglosphere cluster; in the UK, the USA, Australia, and New Zealand, migrants are underrepresented in prisons and jails.

As I’ve written before, this does not conclusively prove that immigrants in the UK commit less crime than natives. If foreign criminals are deported rather than being incarcerated in the UK, this could lead to fewer criminal immigrants in prison than criminal natives.

It seems like deportation does happen in at least some cases; about 3,500 foreign national criminals are deported from the UK each year. However, I don’t think this is incredibly significant, given the following:

The foreign population in prison has been relatively constant from 2014 to 2024, suggesting that each year, the deported population is (roughly) replaced with new prisoners. So we have ~3,500 new prisoners each year.
The average prison sentence length is 20 months, half of which is served in prison. So let’s say the average prisoner is in prison for about a year.
Thus, if no prisoners were deported, you’d have about 3,500 more people in prison that year - and the years following. This would increase the foreign criminal population to ~14,000.
There are about 100,0

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Migration Literature Review