Weill retired in 2019 as president of the Food Research & Action Center, a position he had held since 1998. At FRAC, he directed efforts to expand participation and improve benefits in key anti-hunger and anti-poverty programs, particularly the Supplemental Nutrition Assistance Program (SNAP); school lunch and breakfast, after-school and summer food programs; the Special Supplemental Nutrition Program for Women, Infants and Children; and income supports like the refundable Child Tax Credit. He previously was program director and general counsel at the Children's Defense Fund, leading efforts in 1985 that produced the first major expansion of the Earned Income Tax Credit and overseeing CDF's Medicaid expansion, child care and child support enforcement reform.
Weill was deputy director and director of federal litigation at the Legal Assistance Foundation of Chicago; litigated major law reform and class action cases in the federal Court of Appeals and U.S. Supreme Court on Social Security, Medicaid, Aid to Families with Dependent Children, SNAP/food stamps and other public benefits issues and the rights of children born out of wedlock. He chairs the board of directors of the Alliance for Justice Action Council and is a member of the boards of OMB Watch and the National Center for Youth Law. Weill serves on the advisory council to the National League of Cities Institute for Youth, Education and Families and was a member of the U.S. delegation to the UNICEF Executive Board.
Weill is a graduate of Cornell University. He earned a law degree at New York School of Law.