Paul Rosen, a former federal prosecutor who served as a senior government executive at the Department of Homeland Security, has joined Crowell & Moring in the the firm’s Los Angeles office. Rosen will serve as a partner in the White Collar & Regulatory Enforcement; Privacy and Cybersecurity; and Government Contracts groups.

With more than a decade of legal and policy experience across all three branches of the U.S. government, Rosen will focus his practice on government investigations, cyber-security and data privacy, and crisis management. He will represent corporate and individual clients enmeshed in major controversies that involve government enforcement actions, internal investigations, and litigation in connection with criminal, civil, regulatory, administrative, transactional, and congressional matters.

In his most recent role, Rosen managed for former Homeland Security Secretary Jeh Johnson the operational, policy, and legal needs of the third largest department in the Executive Branch, advising on a broad range of national security issues—from counter-terrorism, cyber-security, border security, and aviation security to trade and travel, immigration and visa policies, and criminal law enforcement matters.

In addition, Rosen has more than four years of experience as a prosecutor and counselor within the Department of Justice. Among his roles, he investigated and prosecuted nationwide, multi-jurisdictional financial fraud matters as a trial attorney for the Department of Justice’s Criminal Fraud Section. He also was counselor to Joseph Biden on the Senate Judiciary Committee.