Courts and scholars have long debated the propriety of judges doing their own research and fact-finding, a debate that has intensified in recent years with the ease of internet research. The U.S. Court of Appeals for the Seventh Circuit has been at the epicenter of that debate.

The controversy boiled over last month in a split decision in which Judge Richard Posner cited his own, extensive Internet research in a prisoner’s civil rights suit. As the dissent put it, “this case will become Exhibit A in the debate” over whether appellate courts can “decide cases based on their own research on adjudicative facts.”