“We didn’t stop burning witches because we invented science; we invented science because we stopped burning witches.” — René Girard

For banks and their investors, the Libor scandal may seem like ancient history. Starting ten years ago, banks paid a series of escalating fines to settle accusations they had rigged benchmark interest rates. Barclays was first out the gates with a $450 million settlement – and its CEO’s head on a stick. UBS followed with a $1.52 billion settlement a few months later, then RBS, then Rabobank. In 2015, Deutsche Bank coughed up a record $2.5 billion. All told, banks paid fines amounting to around $9 billion worldwide. They paid their dues, some replaced senior executives, and collectively they moved on.

For some former employees, though, that wasn’t the end of the story.

After the financial crisis, authorities had been under pressure to make individual bankers accountable for the economic collapse they were perceived to have caused. Attributing the financial cr…