Columbia subject headings:
Harvard subject headings:
Police misconduct--United States--History--20th century.
Police patrol--United States--Surveillance operations--History--20th century.
Police patrol--United States--Surveillance operations.
Police--Complaints against--United States.
Political crimes and offenses--Investigation--United States--History--20th century.
Political crimes and offenses--United States
Political persecution--United States--History--20th century.
Princeton subject headings:
Police patrol--United States--Surveillance operations.
Police--United States--Complaints against.
Political crimes and offenses--United States.