Pima County has five Supervisory Districts, of which 3 are partially in LD 20. Pima County determines its own district boundaries. Supervisors are elected by district and the Chair is chosen by the Board. Most of LD 20 is in District 5. the western part is in District 3 and small urban part in District 2. Supervisors are elected for four-year terms.
You can influence what happens at the county level by contacting your supervisor and watching Supervisor meetings. They meet usually on alternate Tuesdays mornings at 9:00 a.m., with other meetings scheduled as needed. You can get agendas and minutes at the Pima County website. Meetings are recorded live on Facebook.
You can also get email newsletters from each supervisor by requesting via email.