• Chart of the Week
  • February 26, 2018

Guilty until proven innocent

A paper in the American Economic Review explored how pretrial detention affects the probability that a criminal defendant will be found guilty.


One out of every five inmates in the United States is awaiting trial. They have not yet been found guilty of a crime. However, they are behind bars, and this means they are more likely to be convicted.

In the February American Economic Review, authors Will Dobbie, Jacob Goldin, and Crystal Yang examine data from over 420,000 criminal defendants from two large urban areas -- Philadelphia and Miami -- and found that pretrial detention significantly increases the probability of being found guilty, mostly via plea deals.


Figure A1 from Dobbie et al. (2018)


The figure above illustrates the path that criminal defendants followed in each city, with the share of defendants who ultimately are detained, reach plea deals, and found guilty. More than a third of defendants in Philadelphia are detained while two-thirds in Miami are jailed before trial.

The authors conclude that, overall, being released after the bail hearing reduces the probability of being found guilty by 14 percentage points. That is driven largely by a reduction in the probability that the defendant will plead guilty, which drops by 10.8 percentage points.

Their paper parallels other research that examines how pretrial detention and monetary bail amounts affect the likelihood of being convicted. It also contributes to an ongoing debate about high incarceration rates among poor and minority defendants — who are less likely to be able to afford bail —  and discrimination in the U.S. criminal system.