Which kind of legal scholarship do judges cite?

A data-driven analysis of Portuguese High Civil Court Decisions

The project “Which kind of legal scholarship do judges cite? A data-driven analysis of Portuguese High Civil Court Decisions” was developed by António Falcão Costa Lopes Janeiro, under the supervision of professors Qiwei Han and Fabrizio Esposito. It had the goal of finding the most cited authors in the Portuguese Supreme Court (“Supremo Tribunal de Justiça”), through the database of the Portuguese Supreme Court judgments – also referred to “acórdãos”, meaning the decision of a court composed of more than one judge.

The database used, consisting of over 60,000 documents, was available on the Instituto de Gestão Financeira e Equipamentos da Justiça I.P. website. However, some problems arose regarding said database. For one, the data has many typing errors (mainly because the documents are handwritten), making it difficult to process and analyze. Furthermore, there isn’t a clear page format in the processes of individual web pages, which makes it hard to build a code that can be applied to every single one that exists. In addition, but the design itself is also in different formats, which in turn means the code will collect “noise” – information that isn’t related to the study – instead of just relevant data.

However, since it is very common in the Portuguese judicial system for judges to cite academic works, such statistical information could be important to reinforce a non-biased juridical system, by taking into account the fact that there are authors who are more prevalently cited – and, consequently, whether a line of doctrine is more commonly defended. This information could also be useful to lawyers, as it would give them the knowledge of which authors’ point of view they should structure their defense around, to strengthen their case.
Therefore, and as much as this project was a first step in understanding better the legal system and amount of data available, more studies are necessary to truly understand and process these types of resources. Such importance has, already, been discussed before, namely in the opinion piece “Para quando a transparência na publicação integral das decisões judiciais em Portugal?”, which can be accessed here: Para quando a transparência na publicação integral das decisões judiciais em Portugal? | Opinião | PÚBLICO (publico.pt)
In this context, professor Fabrizio Esposito has been collaborating with professor Qiwei Han (Nova SBE) on the use of automated and semi automated data analysis in legal research. Currently, the team’s focus is on adapting existing software to carry out “Semi-automated systematic reviews of legal literature and studies”.