Harvey Wiley in History of Drugs in America
Dr. Harvey Wiley (1844–1930) was a chemist who became one of America's most prominent advocates of food and drug purity during the Progressive Era. He helped to pass the 1906 Pure Food and Drug Act and then became the federal government's chief enforcer of the new law.
Dr. Wiley considered caffeine to be a type of poison, declaring in 1910 that "coffee drunkenness is a commoner failing than the whiskey habit. [...] This country is full of tea and coffee drunkards. The most common drug in this country is caffeine."
The next year, he led a federal lawsuit against Coca-Cola, charging that the unnatural presence of caffeine in the drink violated the Pure Food and Drug Act. Coca-Cola won the case.