What the judge had for breakfast

Legal realism is what the judge had for breakfast, right? This is what people used to say when they wanted to make fun of legal realism. The origins are unclear, but the closest I have come to its origins is this:

Study of particular personalities becomes essential to the advocate, and so, important for Jurisprudence if it is not to ignore the facts of life. In the case of a particular judge subject to dyspepsia, the unfortunate effects of a particular ill-advised breakfast do alter the advocate's practical problem. I confess to total inability to understand why, when the subject of study is the effect of advocacy and the bearing of the advocate’s work on the result of cases and the growth of law, such matters should be regarded as either unilluminating or indecent to discuss.

K.N. Llewellyn, On Reading and Using the Newer Jurisprudence (1940) (requires subscription).

Well, it now turns out that this may not be such a joke after all. Here is the abstract of an article to be published in the Proceedings of the National Academy of Science:

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.

Here is the source.