What factors influence crime rates? US statistics for 2025 show a sharp drop from 2024 in murders and other violent crimes, the sharpest on record since 1936. President Donald Trump’s supporters have held up tough policing as the prime cause.
Yet, barring a covid blip, a downtrend has been in evidence since the early 1990s. In their 2005 book Freakonomics, Steven Levitt and Stephen Dubner assigned a major role to legalized abortion.
After the judiciary’s Roe vs Wade ruling of 1973 that made it legal US-wide, they argued, the birth rate of unwanted children collapsed, leaving fewer youth exposed to rough lives.
This link was controversial, of course, given America’s political divide over pregnancy termination. In fact, that judgement was overturned by the US Supreme Court in 2022.
Many Republican-ruled states have since banned abortion, in contrast with Democrat-run ones. If party loyalties hold more or less firm for about two decades, split-run data may let analysts test the abortion theory against crime records.
That’s a long wait, but that is also partly the point. Politicians have an interest in showing near-instant results. Academia, however, must take a longer view.