A Bloomington man was sentenced to 20 years in prison yesterday for a conviction on his eleventh driving under the influence case. Prosecutors say 49-year-old William Dietrich's license had been revoked since 1983. His first DUI conviction was in 1982. Officials said Dietrich was also convicted twice in 1986 and once each in 1989, 1991, 2000, 2002, 2005, and 2007. Dietrich had previously received eight years in prison for a Class X conviction in Tazewell County.