Steven David Levitt (born May 29, 1967) is an American economist and co-author of the best-selling book Freakonomics and its sequels (along with Stephen J. Dubner). Levitt was the winner of the 2003 John Bates Clark Medal for his work in the field of crime, and is currently the William B. Ogden Distinguished Service Professor of Economics at the University of Chicago as well as the Faculty Director and Co-Founder of the Center for Radical Innovation for Social Change at the University of Chicago[2] which incubates the Data Science for Everyone coalition.[3] He was co-editor of the Journal of Political Economy published by the University of Chicago Press until December 2007. In 2009, Levitt co-founded TGG Group, a business and philanthropy consulting company.[4] He was chosen as one of Time magazine's "100 People Who Shape Our World" in 2006.[5] A 2011 survey of economics professors named Levitt their fourth favorite living economist under the age of 60, after Paul Krugman, Greg Mankiw and Daron Acemoglu.[6]
Levitt has published over 60 academic publications, studying topics including crime, politics and sports, through the framework of economics. For example, his An Economic Analysis of a Drug-Selling Gang's Finances (2000) analyzes a hand-written "accounting" of a criminal gang, and draws conclusions about the income distribution among gang members. His most well-known and controversial paper (The Impact of Legalized Abortion on Crime (2001), co-authored with John Donohue) posits that the legalization of abortion in the US in 1973 was a major causal factor in the considerable reduction in crime that followed approximately eighteen years later.
Revisiting a question first studied empirically in the 1960s, Donohue and Levitt argued that the legalization of abortion could account for almost half of the reduction in crime witnessed in the 1990s.[10] Their 2001 paper sparked much controversy, to which Levitt has said
". . . John Donohue and I estimate maybe that there are 5,000 or 10,000 fewer homicides because of it. But if you think that a fetus is like a person, then that's a horrible tradeoff. So ultimately I think our study is interesting because it helps us understand why crime has gone down. But in terms of policy towards abortion, you're really misguided if you use our study to base your opinion about what the right policy is towards abortion"[11]
In 2003, Theodore Joyce argued that legalized abortion had little impact on crime, contradicting Donohue and Levitt's results.[12] In 2004, the authors published a response,[13] in which they claimed Joyce's argument was flawed due to omitted-variable bias.
In November 2005, Federal Reserve Bank of Boston economist Christopher Foote[14] and his research assistant Christopher Goetz, published a paper,[15] in which they argued that the results in Donohue and Levitt's paper were due to statistical errors made by the authors. When the corrections were made, Foote and Goetz argued that abortion actually increased violent crime instead of decreasing it.
In January 2006, Donohue and Levitt published a response,[16] in which they admitted the errors in their original paper, but also pointed out that Foote and Goetz's correction was flawed due to heavy attenuation bias. The authors argued that, after making necessary changes to fix the original errors, the corrected link between abortion and crime was now weaker but still statistically significant.
In 2019, Levitt and Donohue published a new paper to review the predictions of the original 2001 paper.[17] The authors concluded that the original predictions held up with strong effects.[18] "We estimate that crime fell roughly 20% between 1997 and 2014 due to legalized abortion. The cumulative impact of legalized abortion on crime is roughly 45%, accounting for a very substantial portion of the roughly 50-55% overall decline from the peak of crime in the early 1990s."