I think they’re probably both right. Breyer and Souter kibitz at HLS.

Apparently some O’Connor clerk thought Breyer was Souter. Fail.

During the many years they served together as associate justices on the U.S. Supreme Court, Stephen G. Breyer ’64 and David H. Souter ’66 were often mistaken for each other by members of the public. But the mixup reached an amusing apogee about a decade ago, when Breyer was invited to lunch by Justice Sandra Day O’Connor’s clerks, when one clerk asked him, “Are you and Justice Breyer often confused?”