Postpartum psychosis and the courts.

Although mental state defenses frequently are raised in cases of infanticide, legal criteria for these defenses vary across jurisdictions. We reviewed outcomes of such cases in states using M'Naughten or model penal code (MPC) standards for insanity, and the factors considered by the courts in reaching these decisions. LexisNexis and Westlaw searches were conducted of case law, legal precedent, and law review articles related to infanticide. Google and other Internet search engines were used to identify unpublished cases. Despite the differing legal standards for insanity among states, the outcomes of infanticide cases do not appear to be dependent solely on which standard is used. The presence of psychosis was important in the successful mental state defenses. This case series suggests that states that use the stricter M'Naughten standard have not been less likely than states with an MPC standard to adjudicate women who have committed infanticide as not guilty by reason of insanity.