As section chief, he was instrumental in executing the FBI’s domestic and international violent crime efforts and designed and implemented the FBI’s body-worn camera program. He also helped reallocate resources to the Oklahoma City Field Office after a Supreme Court decision increased the FBI’s investigative responsibilities in Indian Country in Oklahoma.

In 2020, Mr. Greenberg was promoted to deputy assistant director of CID, where he led sections that deal with financial crimes, public corruption, civil rights, and the FBI’s covert operations. Notably, he led the charge to elevate investigating hate crimes because of the continuous increase in incidents nationwide.