This HFG report, authored by Dr. Vally Koubi, analyzes the existing research on the relationship between climate and conflict. It includes key takeaways, policy recommendations, and areas for future study.

In Government Legitimacy, Social Solidarity, and American Homicide in Historical Perspective, Randolph Roth, professor of history and sociology at The Ohio State University, argues that shifts in citizens’ beliefs about the legitimacy of their government and the character of political leadership, feelings of affinity for — or alienation from — fellow citizens, and acceptance or resentment of their place in the social order affect the frequency with which Americans kill each other.

In this report, authors James Austin and Richard Rosenfeld forecast very modest increases in violent crime and then a flattening trend by 2025 as well as a continuation of the longstanding decline in property crime. They use their forecasting models to project the effect of decreasing the nation’s declining rate of imprisonment by an additional 20%. Such a policy decision, they conclude, would not lead to significantly higher crime rates. 

This report examines the effects of a small set of factors on violent and property crime rates in Chicago. The authors used a statistical model to forecast crime rates through 2025. Both violent and property crime are forecast to drop through 2025. In addition, the report finds that were Illinois to reduce its imprisonment rate by 25%, the effect on Chicago’s rate of violent crime would be negligible. No association was found between imprisonment rates and property crime. 

Florida has benefited from the national drop in crime that began in the early 1990s. Its growth in incarceration also paralleled the steady national imprisonment rise of the last forty-five years. Policy makers would benefit from defensible projections of future trends in crime, and especially from estimates of the effect that further reductions in the number of people in jail and prison might have on those trends. The authors of this study developed quantitative models of the effects of various demographic and economic factors, as well as the imprisonment rate, on Florida’s past crime rates. They then used these models to project crime trends into the 2020s.

In The Opioid Epidemic and Homicide, criminologists Joel Wallman, Richard Rosenfeld, and Randolph Roth find a “substantial association” between opioid overdose deaths and homicide, with variations by race and geography.

In Is Bail Reform Causing an Increase in Crime?, criminologists Don Stemen and David Olson examine crime rates in eleven states and cities that adopted bail reforms, finding “no clear or obvious pattern” connecting bail reform to changes in violent crime rates.

In International Sanctions against Violent Actors, Dursun Peksen observes that international sanctions rarely operate on the ground as their proponents intend. They succeed in only about 30 percent of cases and often prompt harsh treatment of a targeted state’s citizens.

HFG’s ‘At the Crossroads’ series concludes with the publication of “Behind the Rise in Gun Violence in New York and Other American Cities,” a compilation of the twelve interviews conducted by Harry Frank Guggenheim Distinguished Fellow of Practice Greg Berman with an essay illuminating common themes and practical approaches to ending such violence.