Bruce Mohler was the founder (in 1920) and long-time head of the Bureau of Immigration, part of the Social Action Department of the NCWC. He was especially active in lobbying for reform of the national origins quota system that governed U.S. immigration law. Mohler opposed the Emergency Quota Act of 1921, as well as the Johnson-Reed immigration bill of 1924. In 1949, he married Dorothy Abts, a faculty member at the National Catholic School of Social Service. Mohler followed NCWC policy in supporting the 1952 McCarran-Walter Immigration Act, because of its restrictions of Communist immigrants, although he maintained reservations about the bill's maintenance of the quota system. In 1953, the Bureau of Immigration was made into a separate department, with Mohler as its director.