BA, Gettysburg College; JD, Yale University
- Subjects Taught: Cybercrime, Electronic Surveillance, and Data Security
- Area(s) of Expertise: Cybercrime, Criminal Law and Procedure, National Security Law, Electronic Surveillance, Data Security, Social Media Policy
- Email: Send an email
Antonin Scalia Law School
George Mason University
3301 Fairfax Dr.
Arlington, VA 22201
Kellen served in the Justice Department for seven years, first as an Assistant United States Attorney (AUSA) in the Eastern District of Virginia, then as Counselor to the Assistant Attorney General for National Security, and finally as Deputy Assistant Attorney General in the National Security Division. As an AUSA, Kellen prosecuted some of the Department’s most consequential computer hacking cases. He received the Attorney General’s Award for a first-of-its-kind prosecution of a Russian-based malware-testing service, called Scan4you. The trial of that case revealed that Scan4you, while operating under the protection of the Russian Federal Security Service (FSB), helped develop some of the world’s most destructive malware, including malware used in the 2013 breach of Target. Kellen also prosecuted Aleksei Burkov, a Russian hacker whose arrest in Israel set off a high profile tug-of-war between Washington and Moscow over his extradition. Burkov was ultimately extradited, convicted, and sentenced to nine years in prison.
As a Deputy Assistant Attorney General (DAAG) in the National Security Division, Kellen oversaw the division’s legal policy and appellate units. As DAAG for legal policy, Kellen was in charge of the Department’s policy on issues such as end-to-end encryption, cryptocurrency, conflicts with EU data protection laws after Schrems II, data breach notification, supply-chain security, and foreign election interference. He also testified before congressional committees, represented the Department on the National Security Council, advised U.S. Cyber Command, approved sanctions, and helped coordinate a whole-of-government response to major cyber incidents. As DAAG for appellate, Kellen advised on the division’s most sensitive cases and oversaw appeals before the Supreme Court, the U.S. Courts of Appeals, and the Foreign Intelligence Surveillance Court of Review.
Prior to joining the Justice Department, Kellen was an associate at Kirkland & Ellis LLP, where he represented major technology companies in civil litigation and government investigations. Kellen served as a law clerk for the Honorable Diarmuid F. O’Scannlain on the U.S. Court of Appeals for the Ninth Circuit, and the Honorable Kenneth M. Karas on the Southern District of New York. He is a graduate of Yale Law School, where he was a Notes Editor on the Yale Law Journal, the managing editor of the Yale Law & Policy Review, and a teaching assistant in constitutional law for Professor Akhil Amar.