The politics and economics of mental health 'parity' laws.

The enactment of the Domenici-Wellstone amendment in September 1996, which calls for the elimination of certain limits on coverage for mental health care under private insurance, is being hailed as a major step forward in the quest for "parity" in mental health coverage. Parity legislation is being introduced in a number of state legislatures and is finding new enthusiasm in Congress. In this paper we consider the efficiency rationale for these laws and examine their likely impact in the era of managed care. We conclude that although such successes represent important political events, they may offer only small gains in the efficiency and fairness of insurance markets.