[3] Riddle was elected to the Colorado House of Representatives from 1911 to 1914, and was part of the 18th and 19th General Assemblies.

[1] Riddle was elected to the Colorado Senate from 1917 to 1920, and represented district 22 including Adams, Arapahoe, Elbert, and Morgan counties.

[3] She was on many committees that addressed labor, child welfare, dairy and farm improvements, and support for destitute mothers.

She established the National Anti-Klan party, and was the only woman Senator in the US to bring forth ratification of the 19th amendment to the US Constitution.

She was an excellent speaker and traveled across the state to teach methods of food preservation and conservation.