Reuben Greenberg was the African American Chief of Police of the Charleston Police Department (South Carolina).  In 1967, he received a BA degree from San Francisco State University and he has two masters degrees, one in public administration and the other in city planning, both from the University of California at Berkeley. He has taught sociology at California State University, political science at the University of North Carolina at Chapel Hill and criminal justice at Florida International University. His career in law enforcement spanned three states before he arrived in South Carolina in 1982. While in California, he served as the undersheriff of the San Francisco County Sheriff's Department. A Savannah, Georgia, he was a major with the city's police department. In Florida, he was chief of police at Opa-Locka and chief deputy sheriff of Orange County, rising to deputy director of the Florida Department of Law Enforcement.

Reuben Greenberg holds memberships in many law enforcement organizations such as the National Association of Black Law Enforcement Executives and the International Association of Chiefs of Police. He is a graduate of the FBI National Academy and an officer of the South Carolina Law Enforcement Officers' Association. He is also a board member of the South Carolina Commission on Racial Relations, the South Carolina Crime Victims Compensation Board and the South Carolina Sentencing Commission. Reuben Greenberg is the author of Let's Take Back Our Streets!

According to Publisher’s Weekly, “during Greenberg's tenure as chief of police of Charleston, S.C., crime has been reduced so sharply that residents jokingly call their city Saintsville. In this rousing call to action against crime, written with a consulting editor of Guideposts , the chief tells what moves he has made to take back the streets in his adopted city from criminals and what he thinks other law officers can do to accomplish the same. Greenberg disputes the contention that law-breakers are victims of circumstance; they commit crimes by choice, he argues, and ought to be prosecuted to the full extent of the law. He also stresses that the function of punishment is, indeed, to punish. This is a book of tough talk from a police chief who firmly believes that we are all accountable for our actions and urges both police and citizens not to surrender to hopelessness about crime.”