A new study in the Quarterly Journal of Economics reveals that nearly half of US federal judges attended crash courses in economics at the conservative-leaning Manne Economics Institute for Federal Judges between 1976 and 1999 — and it changed how they behaved on the bench.

Reviewing more than a million circuit and district court rulings, the study’s researchers found that after attending the popular economics “training,” judges ruled against regulators more often and imposed more severe sentences against criminals.

This isn’t the first evidence that “law and economics” courses push judges to the right. The same authors previously found that Manne attendees were less likely to rule in favor of environmental or union regulations and gave longer prison sentences to federal defendants.