Judges tend to give favourable rulings after lunch

But as the time passes, they are less likely to give parole until they eventually give hardly any positive outcomes for prisoners, the researchers found. According to them, their findings show that even experts are not immune to outside influences and the study could hold for other kinds of decision making, the Telegraph reported.

“Indeed the caricature that justice is what the judge ate for breakfast might be an appropriate caricature for human decision making in general,” said the researchers.

For their study, the team led by Professor Jonathan Levav analysed more than 1,000 decisions made over 50 days by judges who ruled on whether to grant parole-related requests from prisoners in four Israeli prisons. They recorded the chronological order of the rulings relative to two food breaks that the judges took each day—one for a morning snack and the other for lunch.

The percentage of rulings in favour of the prisoners fell gradually from about 65 per cent to nearly zero in each of the three decision-making sessions demarcated by the two breaks. It then abruptly leapt back to 65 per cent immediately after the breaks, suggesting that prisoners whose cases were heard at the start of the day or soon after a break had an advantage over other prisoners.

The findings bolster a view that judicial reasoning is hardly ironclad and may sometimes be prone to bias, according to the authors.

“Our findings add to the literature that documents how experts are not immune to the influence of extraneous irrelevant information,” said the authors.