Sean P. McDonnell

About Sean

Sean McDonnell is a partner in Mayer Brown's Washington D.C. office and a member of the global Litigation & Dispute Resolution practice. Previously, Sean was an Assistant United States Attorney (AUSA) in the U.S. Attorney’s Office for the Eastern District of Pennsylvania.

During his tenure as a federal prosecutor, Sean first-chaired several jury trials to verdict and oversaw large-scale investigations, including complex wiretap and forensic financial investigations. He prosecuted a variety of cases involving, among other things, tax fraud, wire fraud, insurance fraud, bank fraud, and public corruption.

Before his stint as an AUSA, Sean was a litigator in Mayer Brown’s Chicago and Washington D.C. offices, where he represented corporate clients in white-collar investigations and various civil litigation matters, including antitrust and securities cases. He regularly teaches courses on managing legal risk at the Wharton School, including a recent “Crash Course on Internal Investigations” seminar.