"It is, of course, the case that no corporation can have engaged in wrongdoing without the active decision of individual officers of that entity," he wrote. "I believe it is also the case that prosecuting individuals has more of a deterrent effect than prosecuting corporations."
Frank's request comes as the government is probing a range of large financial institutions for a variety of issues. On Wednesday, the Swiss bank UBS agreed to pay roughly $1.5 billion to settle charges that its traders engaged in "extensive" efforts to rig a key interest rate — the London Interbank Offered Rate (Libor). That announcement did include criminal charges, as the Justice Department said it charged two former traders with conspiracy, with one of them also facing charges for wire fraud and price fixing.