The U.S. Marshals Service Sex Offender Investigations Branch (SOIB) was created following the passage of the Adam Walsh Child Protection and Safety Act (AWA) in July 2006. The Adam Walsh Act names the U.S. Marshals Service as the primary federal agency to assist state and local law enforcement agencies with tracking and arresting non-compliant sex offenders nationwide. The Adam Walsh Act also provides a statute for Deputy U.S. Marshals to prosecute sex offenders federally for failing to register as a sex offender.

The mission of the SOIB is to ensure the safety of communities and children across the country, and implement an aggressive enforcement strategy against non-compliant sex offenders that travel across state line and fail to register.

Deputy U.S. Marshals of the SOIB assist numerous local law enforcement agencies throughout the Commonwealth of Massachusetts. In 2011, SOIB established a highly successful task force known as the Sex Offender Apprehension Program (SOAP) with the Boston Police Department.