Question: Robert L. DuPont, is a national leader in marijuana policy, drug policy and treatment, he was second White House Drug Czar from 1973 to 1977 under former Presidents Richard Nixon and which American politician who served as the 38th President of the United States from August 1974 to January 1977?
Sentence (from "Robert Warshaw"): He previously served as Chief of the Rochester Police Department.
Relevant evidence: No