[1] Moriarty settled in Sedalia, Missouri, and became active in state and local politics.

She was appointed to run the local license fee office by Governor Joe Teasdale in 1977.

She caused a stir early in her term when she announced that the Official Manual State of Missouri, published by the secretary of state and often referred to as the "Blue Book" because of its traditional blue cover, would instead be published with a mauve cover as a tribute to the role of women in Missouri politics.

[8] In 1994, Moriarty was the subject of investigations due to financial practices, such as making long distance calls to family members.

[10][11] Consequently, Governor Mel Carnahan called for a special session on September 22, 1994, so that the Missouri House of Representatives could consider impeaching Moriarty.

On December 12, 1994, the court voted unanimously that Moriarty had committed impeachable offenses, forcing her from the office.

Moriarty reportedly considered running for governor in 2008, but did not meet the filing deadline.