In 2011 a study published in the Proceedings of the National Academy of Sciences in an article entitled Extraneous Factors in Judicial Decisions by Shai Danziger, Jonathan Levav, and Lioria Avvan-Pesso, (the "DLA" study) alarmed many of us by calling into question the supposed wisdom and impartiality of judicial decisionmakers.
Are judicial rulings based solely on laws and facts? Legal formalism holds that judges apply legal reasons to the facts of a case in a rational, mechanical, and deliberative manner. In contrast, legal realists argue that the rational application of legal reasons does not sufficiently explain the decisions of judges and that psychological, political, and social factors influence judicial rulings. We test the common caricature of realism that justice is “what the judge ate for breakfast” in sequential parole decisions made by experienced judges. We record the judges’ two daily food breaks, which result in segmenting the deliberations of the day into three distinct “decision sessions.” We find that the percentage of favorable rulings drops gradually from ≈65% to nearly zero within each decision session and returns abruptly to ≈65% after a break. Our findings suggest that judicial rulings can be swayed by extraneous variables that should have no bearing on legal decisions.
According to Andreas Glockner, The irrational hungry judge effect revisited: simulations reveal that the magnitude of the efffect is overstated (Cambridge Univ Press 2023), this study is flawed, in that an alternative explanation for the change in rulings as the morning proceeds readily exists.
DLA found that the probability of a favorable decision drops from about 65% in the first ruling to almost 0% in the last ruling within each session. The rate of favorable rulings returns to 65% in the session following the break. DLA argue that this effect of ordering shows that judges are influenced by extraneous factors and they speculate that the effect is caused by mental depletion. The argument is that, after repeated decisions, judges become exhausted, hungry or mentally depleted and use the simple and less effortful strategy to stick with the status quo by rejecting the request resulting in what could be called an “irrational hungry judge effect”.
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One crucial assumption permitting conclusions concerning the effect of case ordering is that case ordering is random or at least not driven by hidden factors that are not taken into account in the analysis. If more severe cases went first, for example, and severe cases at the same time reduced the likelihood of favorable decisions, spurious correlations could result.
....DLA report that favorable rulings take longer than unfavorable rulings. The number of cases completed in each session varies between 2 and 28 and DLA present rulings for 10 to 13 cases within each session, with the last ruling having a probability of zero (or in one case close to zero) to be favorable, respectively. Consequently, the number of observations within each session decreases with ordinal position and the last observations in a session are likely to consist of a few observations only. Considering that favorable rulings take longer than unfavorable rulings, the dropout is not random. On average, sessions that consist of mainly unfavorable decisions will allow judges to make many rulings. Therefore, in the reduced sample of observations constituting the data for higher ordinal positions, the relative frequency of rulings from sessions with mainly unfavorable decisions increases.
Judges have to finish cases before they take a break. To avoid starving, they are likely to avoid starting potentially complex cases (or sets of cases) directly before the break. It seems reasonable to assume that simple surface features that are available before investigating the case in detail (e.g., amount of material, kind of the request, representation by an attorney, some specifics of the attorney, the prison, or the prisoner) allow judges roughly to estimate the time the next case will take above chance level.
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The analyses reported here indicates that the effect of serial order and mental depletion is overestimated in the original work by DLA. Rational time management concerning when to take a break and effects of non-random ordering of cases with represented prisoners going first ... are lumped together with potential effects of serial order and mental depletion so that the latter are overestimated.
