Vanderbilt Law Review

First Page



On January 2, 1986, Judge Richard Posner of the United States Court of Appeals for the Seventh Circuit announced to an astonished legal profession, not to mention the unsuspecting attorneys-of-record, that, in the future, the Seventh Circuit would decide whether to grant or deny a preliminary injunction by applying the following simple formula:

P x Hp > (1-P) x Hd

With one fell swoop of his algebraic-judicial pen, Judge Posner not only stirred the deepest math anxieties of the practicing bar, but revolutionized preliminary injunction law. Despite Judge Posner's protestations that his simple formula was not "offered as a new legal standard," preliminary injunction law will never be the same.

This Article addresses the transcendental question raised by this preliminary injunction formula: What hath Judge Posner wrought? On sober reflection, it is abundantly clear that Judge Posner's preliminary injunction formula sprang full-blown from the head of an academic-economist turned judge. The preliminary injunction formula is a logical extension of Judge Posner's desire to impose econometrics on all aspects of the law. Dissatisfied with the untidiness of mere mortal judicial decision making, Judge Posner intends to rationalize the law by Benthamizing it--by subjecting the law to a twentieth century version of felicific calculus."

This Article sounds the alarm concerning Judge Posner's seemingly innocent mathematical foray into preliminary injunction aw. Judge Posner's formula should not be viewed simply as an"intellectually diverting" exercise, but should be recognized for what it truly is: the camel's head in the tent. Judge Posner long has been an advocate of market analysis in appropriate substantive legal contexts such as antitrust, tort, corporation, securities, and tax law.' With his preliminary injunction formula, however, he has crossed the great divide between market and nonmarket applications of econometrics. If Professor Posner has his druthers as a judge, he will reduce all of civil procedure to a neat set of formulas."

This Article argues that Judge Posner's efforts to Benthamize civil procedure are an abomination in theory and practice. Judge Posner's preliminary injunction formula should be "bur[ied] with kindness," and any further attempts to quantify civil procedure should be resisted swiftly and sternly. Econometrics should be relegated to limited substantive applications and not engrafted onto inappropriate procedural motions.

Part II of this Article outlines the short happy life of formula Posner. This section first discusses Judge Posner's articulation of the preliminary injunction formula in American Hospital Supply Corp. v. Hospital Products Ltd.1" and then describes the formula's reception in the Seventh Circuit and among the district courts. Far from being repudiated outright, Judge Posner's formula has taken shallow root at the trial court level. Significantly, however, trial judges have manifested groping uncertainties in utilizing the new-fangled formula. Consequently, recent Seventh Circuit decisions amply demonstrate the many problems inherent in quantifying the preliminary injunction process.

Part III explores the roots of Judge Posner's preliminary injunction formula and illustrates that the formula is a logical extension of Judge Posner's lifelong commitment to rationalizing legal substance and procedure. This section demonstrates that Judge Posner is an intellectual heir of Jeremy Bentham, who attempted to develop a felicific calculus of the law, and Judge Learned Hand, who attempted to develop algebraic torts. More recently,Professor John Leubsdorf has provided Judge Posner with an economic analysis of preliminary injunctions, stressing minimization of error through probabilistic calculations. This section further demonstrates that these intellectual strands have merged in Professor Posner's writing and Judge Posner's decisions.' More importantly, however, this section exposes the problems associated with applying econometric methodology to civil procedure, including the methodology's reliance on unsound premises, uncertain probabilistic assessments, implicit subjectivity, and illusory objectivity.

Part IV demonstrates that Judge Posner's preliminary injunction formula is not an isolated decisional novelty. Instead, the formula represents an initial foray into mathematical civil procedure. Unless the formulaic approach is reproved swiftly, the legal profession can expect Judge Posner to announce additional procedural formulas. Judge Posner's efforts to Benthamize civil procedure should be rejected because they undermine principled decisionmaking. This Article is not merely about preliminary injunctions." Nor is it a roaming discussion of the ever-burgeoning field of law and economics.' Rather, it is an article that rejects and warns of the incipient Benthamization of civil procedure. In the final analysis, this Article is an attempt to supply reasoned argument to one district judge's plaintive response to Judge Posner's preliminary injunction formula: "[I]f it ain't broke, don't fix it."'