One apple a day keeps the bad ruling away - extraneous factors in judicial decisions
Updated: Jan 28, 2022
When judges make repeated sequential rulings, they simplify their decisions in cases with similar legal characteristics and rule more in favor of the status quo over time, but they can overcome this tendency by taking a food break.

In their study, Danzinger and his colleagues tested the common caricature that justice is “what the judge ate for breakfast” and concluded that, indeed, this caricature might be appropriate and not only for legal decision-making but also general human decision-making.
The researchers' results indicate that extraneous variables can influence judicial decisions, which supports the growing body of evidence that points to the susceptibility of experienced judges to psychological biases. The findings of the study underpin the view that legally irrelevant situational determinants—in this case, merely taking a food break—may lead a judge to rule differently in cases with similar legal characteristics.
The research examined 1,112 judicial rulings by 8 Israeli judges, made over 50 days in 10 months, all regarding parole requests. Every day a judge considered 14–35 cases. The study's hypothesis was that sequential choices and the apparent mental depletion that they evoke increase people’s tendency to simplify decisions by accepting the status quo. In a legal context, it means that making repeated rulings can increase the likelihood of judges simplifying their decisions. The researchers speculated that as judges advance through the sequence of cases, they will be more likely to accept the default, status quo outcome that denies a prisoner’s request. In their data, the researchers recorded the two daily food breaks that the judge took —a late morning snack and lunch — which served to break up the day’s deliberations into three distinct “decision sessions.” Such a break may have replenished mental resources and executive functions by providing rest, improving mood, or by increasing glucose levels in the body.
The analysis of the results showed that the likelihood of a favorable ruling was greater at the very beginning of the workday or after a food break than later in the sequence of cases. The likelihood of a ruling in favor of a prisoner spiked at the beginning of each session— the probability of a favorable ruling steadily declined from ≈0.65 to nearly zero and jumped back up to ≈0.65 after a break for a meal. In conclusion, the repeated rulings depleted the judges’ mental resources, causing judges to have a higher likelihood of granting parole in the first cases after a break.
These results suggest that when judges make repeated rulings, they show an increased tendency to rule in favor of the status quo. The study also pointed out that the judges can overcome this tendency by taking a break to eat a meal, consistent with previo us research demonstrating the effects of glucose on mental resource replenishment.
Although the researchers’ focus was on expert legal decisions, the exact mechanism is likely to present in other forms of decision simplification strategies for experts in other important sequential decisions or judgments, such as legislative, medical, financial, and university admissions decisions.
Cheat sheet for busy lawyers
Title
Extraneous factors in judicial decisions
Authors
Shai Danziger, Jonathan Levav, and Liora Avnaim-Pessoa
Year of publication
2011
Theoretical/ Conceptual Framework
Biases in the ruling process. The researchers empirically tested this caricature in the context of sequences of parole decisions made by experienced judges (mean experience=22.5 y, SD=2.5) and, in so doing, demonstrate how extraneous factors can sway highly consequential decisions of expert decision-makers.
Research Question(s)/ Hypotheses
Sequential choices and the apparent mental depletion that they evoke increase people’s tendency to simplify decisions.
Methodology
1,112 judicial rulings, collected over 50 days in 10 months, by eight Jewish-Israeli judges (two females) who preside over two different parole boards that serve four central prisons in Israel.
Analysis/Results
The likelihood of a ruling in favor of a prisoner spiked at the beginning of each session— the probability of a favorable ruling steadily declined from ≈0.65 to nearly zero and jumped back up to ≈0.65 after a break for a meal.