[6] Coming from a background of farming, Sinner served as president of the Red River Valley Sugarbeet Growers Association Board from 1975 to 1979.

During that time, he chaired an ad hoc farm commodity group that was responsible for funding and constructing the greenhouse complex and the Northern Crops Institute at North Dakota State University in Fargo.

During his time on the State Board of Higher Education, he helped craft the "Tri-college" system currently used by NDSU, MSUM and Concordia College, Moorhead.

[9] The North Dakota Supreme Court settled the issue in Sinner's favor on January 5, 1985, one day before Olson would have vacated office anyway.

[9] Olson failed to comply with the decision and did not vacate the governor's office until the following day, but Sinner's term was retroactively recognized to have begun on January 1.

[8] Following his second term, Sinner served as Vice President of Public and Government Relations for the Crystal Sugar Company in Moorhead, Minnesota.