Increased investment in public schools pays off through reductions in adult crime, according to a new University of Michigan study.

The Education Policy Initiative brief, Public School Funding, School Quality, and Adult Crime, investigates the correlation between increased funding for public schools and reduced crime rates. Using data from the Michigan Department of Education, Center for Educational Performance, National Student Clearinghouse and Michigan State Police, the authors tracked two groups of students from kindergarten to adulthood.

"Michigan's school funding equalization process led to otherwise similar students receiving drastically different funding amounts during elementary school," the report says. "Some students with 'luck' attended elementary school in a school district and year in which the state assigned large increases in spending in order to equalize funds across districts."

The authors, E. Jason Baron, Joshua Hyman and Brittany Vasquez, compared the outcomes of the "treated" students with "control" students—those attending schools in districts and years that did not receive large funding increases.

Tracking the outcomes of these two groups of students, the researchers come to several conclusions:

• Students who attended better-funded elementary schools were taught by teachers with greater experience and earning higher salaries, were in smaller class sizes, and attended schools with a larger number of administrators such as vice principals.
• Students who attended better-funded schools were 15% less likely to be arrested through age 30.
• A likely reason for the observed reduction in adult arrests is that students in better-funded schools had better academic and behavioral outcomes and higher educational attainment.
• The reductions in adult crime alone generate social savings that exceed the costs to the government of increasing school funding.

The authors propose two key policy takeaways. First, they emphasize that increases in public school funding early in children's lives can reduce adult crime.

"While many policies focus on the crime-deterring effects of additional policing or tougher criminal justice sanctions, our findings highlight that early investments in children's lives can prevent contact with the adult criminal justice system," the researchers say in the study. "Specifically, our results show that improving public schools can keep children on a path of increased school engagement and completion, thereby lowering their criminal propensity in adulthood."

Second, the authors highlight that increases in public school funding generate important benefits to society, not just improved academic outcomes and educational attainment. Such investments, they add, "have benefits that extend beyond their intended purpose and recipients."