As chairman of the interdiocesan Southern California Immigration Task Force, O'Connell helped coordinate the church's response to immigrant children and families from Central America in recent years. He also sponsored the enrollment of several young immigrants in Catholic schools, several of whom have advanced to college.
At the national level, he was chairman of the Subcommittee on the Catholic Campaign for Human Development of the U.S. Conference of Catholic Bishops. "This is L.A. Aux. Bishop David O'Connell, with one of my young clients," immigration attorney Linda Dakin-Grimm wrote on Twitter alongside a photo. "Bishop Dave ... was there for every child and family I have represented. Always. Helping, supporting and generally being the face of Jesus for me and many many others."