​ Prior to serving in the Montana Senate, Diane served in House for four terms. There, she secured $280,000 for the initial expansion of Traveler's Rest State Park in Lolo. A tireless legislator, in the 2017 legislative session alone Diane introduced a package of bills making it easier for prosecutor's to charge and try sexual assaults, secured funding to reduce the waiting list for services for child with autism and sponsored a bill to regulate e-cigs, making them illegal for minors. ​ Diane has spent a lifetime working to preserve Montana's history while striving to ensure its strong future. Diane retired from the Historical Museum at Fort Missoula and in 2017, received the life time achievement award from the Montana Historical Society naming her a "Guardian of Montana Heritage".

​ Diane serves on the Montana DPHHS Opioid Task Force, the Board of Orchard Homes Country Life Center and is a member of Target Range Homeowners Association and Gov. Steve Bullock's Equal Pay for Equal Work Task Force.