She first appeared in September 10, 1972 in which she has a fight with her husband, Clinton, over her rights as a woman. She finds that her recently acquired feminist beliefs clash with his idea of how a wife should behave, and she promptly walks out on him. She catches a ride with Mike Doonesbury and Mark Slackmeyer who happen to be traveling cross-country on motorcycle at the time, and travels with them back to Walden Commune. They allow her to stay in exchange for her helping out with the Commune; there she spent several years living with the other characters while running a day-care service for local children (whose parents often weren't too thrilled when their little girls came home talking about Women's Rights). While running Walden Day Care, Caucus sent off applications to several real-life law schools (whose actual students petitioned the schools to accept her as a student). She eventually accepted an offer from Boalt Hall, and moved to California. She shared an apartment with Ginny Slade while there, and helped Ginny in an unsuccessful bid for the United States Congress.
After becoming a lawyer, Joanie spent many years working for Congresswoman Lacey Davenport, and married Rick. She also reconnected with her daughter J.J., whom she hadn't seen since she left her family in 1972. Joanie felt incredibly guilty over this, but she and J.J. have reconciled.
Joanie is one of the more down to earth characters of the strip. She had an almost maternal relationship with the others at the commune, and appears to have moderate political beliefs. She worked for Davenport despite the fact that Lacey was a Republican and Joanie was a Democrat, considering that Lacey's upstanding character was more important than her politics.
In January 2009, Joanie describes herself as a 70 year old retired civil servant born in 1938. She and Rick Redfern still live in Washington DC.
She currently (April 2013) works as an aide to Elizabeth Warren after Warren's successful Senate campaign.