Erin O’Connell-Diaz served two terms as a Commissioner of the Illinois Commerce Commission. During her terms of office Illinois became a leader in the nation for its rail safety education and grid modernization programs. She also steered the state to become home to one of the nation’s most successful competitive electric and gas markets. She served as Chair for the ICC committees on Consumer Outreach, Water, Electric Vehicle Initiatives, and Transportation/Rail-Safety. She was instrumental in collaborative process focused on Illinois’ development of a competitive electric supply market. O’Connell-Diaz was the lead regulator to several USAID/Department of Energy partnerships programs, notably in Brazil and Kosovo. Currently she is a member of the Harvard Electric Policy Group and the New Mexico State University Public Utilities Advisory Council.
A veteran regulator, O'Connell-Diaz began her public service career as an Illinois Assistant Attorney General–General Law Division, then as an Administrative Law Judge for the Illinois Commerce Commission, culminating in her appointment as the Assistant Director-Administrative Law Division. In that role, she managed the oversight operations of the Judge’s Division while carrying a full docket of active cases assigned to her. Throughout her career she has handled extremely high profile cases of significance involving a full spectrum of issues involving: rate cases for the regulated water, electric, gas, and telecommunications entities; creation of competitive electric and gas markets and customer choice.