A man accused of shooting a Rusk County deputy to death has entered a plea of not guilty. Doug Nitek withdrew a mental insanity plea during a Monday hearing in northwestern Wisconsin. Nitek also withdrew his motion requesting a change of venue. The defense had originally argued the move out of the county would be required if a non-biased jury was to be seated. A follow-up to deal with several issues has been scheduled for June 4th in St. Croix County. A September trial date has been set for Nitek.