Columbia Public Law & Legal Theory Working Papers

Document Type



Revision posted 06/06/13


The best interest of the child standard has been the prevailing legal rule for resolving child custody disputes between parents for nearly forty years. Almost from the beginning, it has been the target of academic criticism. As Robert Mnookin famously argued in his 1975 article, “best interests” are vastly indeterminate – more a statement of an aspiration than a legal rule to guide custody decisionmaking. The vagueness and indeterminacy of the standard make outcomes uncertain and give judges broad discretion to consider almost any factor thought to be relevant to the custody decision. This encourages litigation in which parents are motivated to produce hurtful evidence of each other’s deficiencies that may have a lasting, deleterious impact on their ability to act cooperatively in the interests of their children.

Despite these deficiencies, the best interest standard has proved to be remarkably durable. Although scholars as well as the American Law Institute have proposed reforms, legislative efforts to narrow the best interest standard have been largely unsuccessful. A few states have adopted a rule that bases custody on parents’ caretaking, but at least one legislature rejected a court-imposed primary caretaking rule, reviving the best interest standard. Repeated efforts by fathers’ groups to enact laws favoring joint custody have usually failed as well. The persistence of best interests presents a puzzle: Are the academic critics wrong or does something other than the utility of the rule explain the reluctance of policymakers to change the status quo?

This Essay confirms the deficiencies of the best interest standard and seeks to explain its persistence despite its obvious limitations. First we argue that the standard’s entrenchment is the product of a gender war that has played out in legislatures and courts across the country for decades. Most substantive reforms have been perceived (usually accurately) as favoring either fathers or mothers, and thus have generated political battles between their respective advocates. The primary front in this war has been a protracted battle over joint custody. Fathers’ groups have lobbied hard for statutes favoring joint physical custody, but they have been opposed vigorously by women’s advocates. As a result of the standoff, little progress has been made (in any direction) toward replacing the best interest standard with a custody decision rule that would narrow and guide the judicial inquiry.

The Essay proceeds as follows. Part II describes the deficiencies of the best interest standard, focusing on the daunting verifiability challenges judges face in applying the standard. Parts III and IV explore the political economy explanation for the persistence of the best interest standard. Part III examines the gender war in legislatures, particularly the repeated battles over joint custody in recent decades. Part IV turns to the struggles to elevate the importance of domestic violence and parental alienation respectively as key factors in applying the standard. Part V focuses on the illusion of mental health expertise as the second key to the entrenchment of the best interest standard. We challenge the assumption that MHPs enable courts to escape the indeterminacy of best interests or guide them toward good custody decisions. Part VI proposes substantive and procedural reforms that can improve custody decisionmaking, potentially resulting in arrangements that conform more closely to the law’s policy goal.

Date of Authorship for this Version

Spring 4-10-2013


domestic relations