A 26-year-old Mt. Vernon man was sentenced yesterday in Jefferson County Court to 5 years in prison for sexually abusing a young girl. Cody Richardson was given credit for 174 days served before he begins serving his prison sentence for Class 2 felony aggravated criminal sexual abuse of a victim under the age of 13. Richardson had pleaded guilty in April to the Class 2 felony in exchange for one Class X felony charge of predatory criminal sexual assault of a child being dismissed and the other reduced to the Class 2 charge. A Class 2 felony is punishable by between 3 and 7 years in prison. Richardson will have to register as a sex offender as part of his conviction. Evidence presented in court showed Richardson committed an act of sexual conduct with the underage victim between February 2015 and January 2016.