Cooper began his law enforcement career with the Gladewater Police Department as a police dispatcher. He was later hired by the Big Sandy Police Department as an interdiction officer in East Texas and trained his own narcotic detection dog. According to his former West Texas Drug Taskforce boss, Barry Cooper was "probably the best narcotics officer in the state and maybe the country." [2]
As a law enforcement officer, Cooper confiscated large amounts of illegal narcotics and drug money. Cooper began to notice that people arrested for possession of marijuana were nonviolent and cooperative, in contrast to people intoxicated on alcohol who "[.] would fight and scream and act crazy." He also noted being deeply affected by the emotional trauma he witnessed while participating in home narcotics raids with other officers attired in raid gear and "more guns than we would ever need." Cooper also stated, "We're sending the kids to the department of human services, we're sending the parents to jail over marijuana. Well, I knew some of these people and I knew they weren't gangsters. I knew they were nonviolent people." He quit law enforcement soon after.