Optimal Tax Theory: The Journey from the Negative Income Tax to the Earned Income Tax Credit

What lessons do we learn from optimal tax theory for the design of income redistribution programs? I modify a standard model of optimal nonlinear income taxation with discrete types to consider differences in both earning ability and the disutility of effort. This gives a role for “workfare” in the optimal tax policy. The existence of screening mechanisms can play a role in explaining non‐participation in cash and in‐kind redistribution programs, including Progresa‐Oportunidades, Lifeline Telephone subsidies, and the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Stigma can increase efficiency of a redistribution program by discouraging participation by individuals near the eligibility thresholds. The Family Assistance Program proposed in the early 1970s lacked adequate stigma for nonworkers, which contributed to a lack of political support. In contrast, the current Earned Income Tax Credit (EITC) provides greater benefits to workers than to nonworkers. Thus the EITC does not require any stigma to screen out individuals who do not work from obtaining benefits. Reasons for separate income support programs for nonworkers and for workers are discussed.