Yung has taught and conducted research in rape and crime law and noticed inconsistencies in the number of rapes reported in a number of cities. Raw numbers of rapes were much lower in some cities than raw numbers of murders, which raised red flags as murder is a less common crime. Yung then learned of media investigations in Baltimore, New Orleans, St. Louis and Philadelphia that documented cases of police departments under-reporting rape statistics.
“Originally I was trying to reconcile why the data was showing such anomalies,” Yung said of the impetus of his paper. “Then I found out about the four cities with documented cases of under-reported rapes, and the more I looked the more red flags there were. There were a number of cities where the numbers didn’t make sense.”
In all, 46 cities, or about 22 percent of the 210 studied police departments responsible for populations of at least 100,000 people, had “substantial irregularities in their rape data, indicating considerable undercounting from 1995 to 2012,” Yung wrote.
“Many people have an incentive for crime to be down on paper,” Yung said of the reason why rape numbers were under-reported.