Identification and treatment of postpartum depression are the increasing focus of state and national legislation, including portions of the Affordable Care Act. Some state policies and proposals are modeled directly on programs in New Jersey, the first state to require universal screening for postpartum depression among mothers who recently delivered babies. We examined the impact of these policies on a particularly vulnerable population, Medicaid recipients, and found that neither the required screening nor the educational campaign that preceded it was associated with improved treatment initiation, follow-up, or continued care. We argue that New Jersey’s policies, although well intentioned, were predicated on an inadequate base of evidence and that efforts should now be undertaken to build that base. We also argue that to improve detection and treatment, policy makers contemplating or implementing postpartum depression mandates should consider additional measures. These could include requiring mechanisms to monitor and enforce the screening requirement; paying providers to execute screening and follow-up; and preliminary testing of interventions before policy changes are enacted.