As I’ve pointed out many times before, private school choice leads to better results for students and the societies in which they reside. The preponderance of the most rigorous scientific evidence suggests that school choice reduces crime and improves student achievement, graduation rates, racial integration, student safety, and civic outcomes. But while the existing evidence is encouraging, it can be thought of as a lower-bound of the true effect of private schooling in general. Here’s why.

As found in my just-released study — coauthored with George Mason University economics graduate student Blake Hoarty — higher-quality private schools are less likely to participate in two of the most highly regulated voucher programs in the U.S., the Milwaukee Parental Choice Program and the Ohio Educational Choice Scholarship Program.