Writer’s choice

Many people envision police as criminal catchers and crime fighters, but in reality, the job is far more complex. List the key historical circumstances or developments that led to the definition of each era of policing. Then choose at least two service roles that are typical responsibilities of the modern police officer. Project into the future: What are some developments that could very well change policing and define one or more new eras in your lifetime?

Must use 4 references!