In a bed at the Santa Rosa Medical Center in San Antonio, periodically plugged into life-support systems, lies Sante Alessandro Bario, 42, once a crack undercover agent for the Drug Enforcement Administration (DEA). He has lain there more than a month, his eyes always open, his brain waves showing no sign of activity, except for occasional convulsions. He is a victim—for reasons that remain mysterious—of the international drug trade.
Bario was a policeman in his native Italy until 1960, when he met his first wife and followed her to Detroit and then Washington. There he got a job as an investigator for...