Anyone who is keen to study what judges actually do must read a new empirical analysis by giants in their respective fields of political science, economics and law. See Lee Epstein, William M. Landes and Richard A. Posner, The Behavior of Federal Judges A Theoretical and Empirical Study of Rational Choice, Harvard University Press (January 2013).* The study looks at the behavior of federal district judges, circuit judges and Justices of the Supreme Court.
As pertinent to this blog, The Behavior of Federal Judges contains a systematic statistical analysis of much of the existing data that has been collected regarding the activities of district judges. The effort is groundbreaking. As the authors point out, the behavior of district judges has largely been ignored. In particular, there has been little empirical (statistical) analysis of what district judges actually do.
I will have more about this book in later posts as it regards district judges, but for now I want to highlight the authors’ analysis of sentencing in the district courts. Here is the essence of the authors’ conclusions regarding sentencing:
To summarize our analysis of sentencing, there is evidence of ideological influence, with judges appointed by Republican Presidents generally imposing heavier sentences when other influences are corrected for. The ideological influence is modest, however, consistent with the overall result of the analysis in this chapter that ideology plays only a small role at the district court level, even though district judges have considerable discretionary authority.
Derived from their statistical analysis, here are the numbers that the authors provide to support the foregoing conclusion:
Differences between Rs and Ds persist when district effects and the other independent variables are held constant, although the differences are small. On average Rs can be expected to sentence defendants to 6.5 more months in prison than Ds in organized-crime drug cases (a 6.6 percent increase), 4.4 months in other drug cases (4.8 percent), 3.5 months in weapons cases (6.4 percent), and 1.1 months in immigration cases (17.7 percent).
While the ideology of the district judge may matter only modestly when viewed from a national perspective, if a Court of Appeals is “politically” homogeneous, then one can expect large differences in how district judges sentence in the circuit where the members of the court of appeals are simpatico as compared with how district judges sentence in a circuit where the members of the court of appeals lacks political homogeneity. Thus, consider this fascinating and striking comparison between the Eighth Circuit (where I hang out) and the Ninth Circuit:
The results are consistent with our previous findings. In three of the four categories, the fraction of Rs in the court of appeals significantly lengthens prison sentences. In organized-crime drug cases, we predict that a district judge in the Eighth Circuit, where more than 80 percent of the [appellate] judges were Rs in the relevant period, would sentence a defendant to 25 more months (a 26 percent increase) than a district judge in the Ninth Circuit, where only 40 percent of the [appellate] judges were Rs. The difference in other drug cases is 19 months (a 22 percent increase), in weapons offenses 8 months (15 percent), and in immigration cases 4 months (65 percent).**
In the coming days, I will offer a critique of the data set used in the authors’ analysis of sentencing at the district court level. I will also suggest a way to address that data problem. Additionally, I will focus on empirical questions pertaining to how district judges in the same district sentence–the question of intra-district disparity. For now, however, it is enough to state that this book should be read by anyone who is serious about studying judicial behavior at the district court level.
*I have earlier written in this blog about my career law clerks and their incalculable value to me. One of those clerks (Jim) tipped me off about this book after reading an excellent review. See Cass R. Sunstein, Moneyball for Judges, The Statistics of judicial behavior, New Republic (April 9, 2013).
** While it is not entirely clear, this analysis appears to be based upon sentences imposed after a trial rather than after a guilty plea. I need to look into that question in more detail because it is very important.