Ruling Out the Rule of Law

63 Pages Posted: 17 Jun 2010  

Kim Forde-Mazrui

University of Virginia School of Law

Date Written: 2007


This Article intends to resolve the debate over whether requiring specificity in legal rules reduces the discretion that legislatures can delegate to executive officials. Part I explains the constitutionalization of legislative specificity as a judicial response to excessive legislative delegation and analyzes recent doctrinal developments in the context of investigatory traffic stops that call into question the efficacy of specificity as a meaningful constraint on the delegation of discretion. The degree of discretion delegated to law enforcement through specific laws in the traffic context appears to be as great as has ever been accomplished through vague laws and, moreover, borders on making police discretion to stop, search, and arrest motorists essentially unfettered. In effect, a peremptory search and seizure is permissible under our constitutional regime and, with respect to motorists, a peremptory traffic stop seems to exist already.

Part II is the centerpiece of the Article. Section II.A addresses the question of what constraints, if any, the void-for-vagueness doctrine places on the capacity of legislatures to delegate discretion to executive officials. The analysis builds on, and goes considerably beyond, the important insights of Livingston and Stuntz, providing a comprehensive and systematic analysis of the relationship between specific rules and enforcement discretion. The inquiry reveals that the degree of enforcement discretion can be understood as a function of both affirmative and negative choices. By “affirmative choice,” I mean the authority of police affirmatively to subject people to enforcement procedures. By “negative choice,” I mean the authority of police to decline to subject people to enforcement procedures even when police are legally authorized to enforce the laws against them. Vague laws tend to vest police with broad discretion, both affirmative and negative. As the analysis further demonstrates, however, specifically defined crimes may delegate as much discretion as vague laws if designed according to certain factors.

Such factors include the seriousness of the criminalized conduct, the difficulty of avoiding the conduct, the social norms surrounding violation of the crime, the rate of law enforcement against such crimes, and the extent to which police and other executive officials have incentives to enforce against commission of the crime for ulterior purposes. Moreover, the affirmative and negative choices created by specific rules are interdependent. That is, expansion of affirmative enforcement options also tends to expand the degree of discretion to under-enforce the law, and increasing negative enforcement authority tends to increase affirmative enforcement choice. Ultimately, as traffic laws exemplify, specific rules can be designed to delegate virtually limitless discretion.

My conclusion, however, is not that specificity in legal rules contributes nothing to constraining the delegation of discretion. Specific rules make the question of whether enforcement is authorized more predictable and less subject to manipulation. Provided that there remains some conduct outside the proscription of a specific rule, enforcement discretion is constrained by the specific rule with respect to that conduct. The discretion-constraining effect of specificity thus depends on whether limits are placed on either the scope of activities that may be criminalized by specific rules or on the authority of executive officials to under-enforce the rules. To the extent that legislatures are permitted to criminalize a broad range of conduct through specific rules and police are permitted to ignore violations of such rules, the requirement of legislative specificity places very little constraint on the delegation of discretion. Without limits on what conduct legislatures may criminalize or on what crimes police may ignore, the requirement of legislative specificity constrains only the form by which legislatures can delegate discretion to executive officials, not the degree of discretion they can delegate.

Section II.B moves beyond the debate over the effect of specific rules on discretion. Based on the analysis in Section II.A, it accepts that specific rules may confer broad discretion and considers the effect that such discretion has on the ability of courts to determine, through antidiscrimination review, whether such discretion is exercised in a discriminatory manner. The analysis reveals an inverse relationship between the degree of discretion created by specific rules and the capacity of courts to monitor the enforcement of such discretion for discriminatory motives, such as race, sex, or religion. The greater the discretion conferred by specific rules, the more difficult it is for courts to determine whether the discretion was enforced in an arbitrary or discriminatory manner. As the degree of discretion tends toward absolute, the effectiveness of antidiscrimination review tends toward zero. The Supreme Court failed to appreciate this insight when, in response to claims of excessive police discretion created by traffic laws, the Court reassured us that the Equal Protection Clause provided a safeguard against discriminatory enforcement. The Court's response is inadequate to the extent that antidiscrimination review is inherently ineffective when applied to decisions that are broadly discretionary. Indeed, the void-for-vagueness doctrine is premised on an understanding that broad discretion makes discrimination largely undetectable. The Court thus seems to have misunderstood the extent to which discretion can be delegated through specific rules and the implications of such discretion for antidiscrimination review. The result is that legislatures effectively have circumvented existing constitutional constraints on delegating discretion, but the Supreme Court has failed to develop an effective doctrinal response.

Part III is suggestive only. It considers some implications of the relationship explored in Part II between specific rules and enforcement discretion and between enforcement discretion and antidiscrimination review. Section III.A considers implications for developing effective constraints against legislative delegation of excessive discretion through specific rules in the context of traffic regulation. Potential approaches include limiting the authority of police to exploit traffic laws for pretextual purposes, requiring the police to justify enforcement practices that have a discriminatory impact, requiring higher enforcement rates, and precluding enforcement of minor traffic violations. While any of these approaches alone or in combination should limit enforcement discretion, the most promising may be the requirement that police only enforce against serious traffic violations. Limiting enforcement to serious violations, such as unreasonably hazardous or reckless driving, would increase police incentives to consistently enforce the law and thereby strengthen the relationship between the law on the books and the enforcement thereof.

Section III.B considers some constitutional implications of these suggestions, primarily concerns over judicial usurpation of legislative and executive prerogative. My emphasis on judicial remedies is not because courts are better able than legislatures to limit legislative delegation of discretion. They are not. The inquiry of this Article, however, concerns whether the void-for-vagueness doctrine limits legislatures that decline to limit themselves. I argue that additional judicial initiatives to limit the delegation of discretion through specific rules should not violate separation-of-powers principles. Legislative supremacy in the criminal law requires judicial checks on delegating discretion, checks among which the void-for-vagueness doctrine serves an important though insufficient role.

Keywords: void for vagueness, discretion, delegation of discretion, legislative supremacy, judicial checks

Suggested Citation

Forde-Mazrui, Kim, Ruling Out the Rule of Law (2007). Vanderbilt Law Review, Vol. 60, No. 5, 2007. Available at SSRN:

Kim Forde-Mazrui (Contact Author)

University of Virginia School of Law ( email )

580 Massie Road
Charlottesville, VA 22903
United States
434-924-3299 (Phone)
434-924-7536 (Fax)

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