Racial Bias Trends in the Text of US Legal Opinions

TL;DR

This study analyzes racial bias in US legal opinions from 1860 to 2009 using word embeddings, revealing persistent bias across regions and time, with no significant change before or after 1950.

Contribution

It applies large-scale word embedding techniques to quantify racial bias in legal language over a long historical period and across regions, providing new insights into implicit bias in law.

Findings

Strong racial bias found in legal opinions across regions and time periods.

No significant difference in bias before and after 1950.

Legal opinions from Northeastern and Southern states show similar bias trends.

Abstract

Although there is widespread recognition of racial bias in US law, it is unclear how such bias appears in the language of law, namely judicial opinions, and whether it varies across time period or region. Building upon approaches for measuring implicit racial bias in large-scale corpora, we approximate GloVe word embeddings for over 6 million US federal and state court cases from 1860 to 2009. We find strong evidence of racial bias across nearly all regions and time periods, as traditionally Black names are more closely associated with pre-classified "unpleasant" terms whereas traditionally White names are more closely associated with pre-classified "pleasant" terms. We also test whether legal opinions before 1950 exhibit more implicit racial bias than those after 1950, as well as whether opinions from Southern states exhibit less change in racial bias than those from Northeastern states. We do not find evidence of elevated bias in legal opinions before 1950, or evidence that legal opinions from Northeastern states show greater change in racial bias over time compared to Southern states. These results motivate further research into institutionalized racial bias.