Sirena Castillo is a litigation partner in the investigations and white collar defense practice and also serves as the firm’s director of . She is resident in the Los Angeles office.

Sirena’s litigation practice focuses on representing banks and other corporate entities during criminal investigations and complex civil litigation, with an emphasis on representing foreign entities in U.S. government investigations.

As Manatt’s director of pro bono, Sirena manages firm pro bono matters and develops the firm’s pro bono and community partnerships nationwide. She also maintains her own active docket of pro bono cases focused on immigration matters. Sirena’s work includes leading the pro bono team representing a class of abused, abandoned or neglected children in California seeking Special Immigrant Juvenile Status (SIJS) protections, and representing asylees before USCIS and in Immigration Court.

Within the firm’s investigations and white collar defense practice, Sirena has represented a wide variety of clients in state and federal courts, including clients in the health care, banking and insurance industries. Her white collar defense practice includes the representation of banks and corporations at all phases of government investigations, including responding to grand jury subpoenas and civil investigative demands. She also conducts internal investigations, both internationally and domestically, for banks and corporate entities in response to allegations of misconduct or to government inquiries. She has experience defending entities in a wide variety of white collar criminal matters, regulatory enforcement matters, internal investigations, and False Claims Act actions.