Ronnie was a college friend of Harry's, a successful, very wealthy corporate lawyer who decided that her true calling in life was to teach at public high school. As a lawyer, Ronnie often acted as a legal advocate for the students in what some argued were completed unrealistic and "off-topic" situations. She handled at least two murder-related trials (one for Steven, one for some students.) Other times, the stories fit the school: one of her first actions as a teacher was to help Danny Hanson organize his students to sue Harvey for emotional abuse, She also helped students get out of various legal jams.
Ronnie soon got over Harry when Senate left the show. She began an on-and-off relationship with Zach Fischer, and accepted a position from the mayor's liaison to be Winslow's new assistant principal after she impressed the school board with her testing techniques. This made Marla, the other candidate for the job, jealous, and angered Scott, who saw Ronnie as a glory-hound who was willing to cut funding for public education in order to further a political career. Zach became jealous of the mayor's liaison who clearly liked Ronnie. Eventually, Ronnie and Scott came to an understanding and were able to avoid budget cuts by cutting all funding on varsity sports. Marla moved on and Zach become a Buddhist and by Season 4 was gone, anyhow. By the time of Season 4, Ronnie has stepped down from her position as vice principal and returned to being a teacher.