Warrant Enforcement in Louisville Metro and the City of St. Louis from 2006 – 2019: A Cross-site Analysis

This study on the role of warrants in local police enforcement was conducted as part of The Research Network for Misdemeanor Justice (RNMJ), a project of the Data Collaborative for Justice (DCJ). that brings together researchers and local government actors to conduct research on lower-level enforcement practices around the country. Warrants direct law enforcement to arrest someone for any number of reasons and are typically issued if someone failed to appear for court, owed a fine, or failed to follow some other court requirement. Courts issue millions of warrants each year but there is little empirical research at the local, state, or national level to help understand the extent to which warrants are driving police enforcement activities.

For this study, researchers at two of the RNMJ sites; Jefferson County, Kentucky (Louisville Metro) and the City of St. Louis, Missouri, conducted an in-depth analysis of the role that warrants were playing in local arrest practices between 2006- 2019. This report is based on two site-specific reports (St. Louis and Louisville Metro) that focus on the individual jurisdictions, and provides a detailed understanding of police warrant enforcement across two jurisdictions with similar social and economic landscapes, including how frequently arrests involve people with open warrants, the charges underlying these warrants, how often the warrant is the sole reason for the arrest, and variance in warrant enforcement by race.

Key Findings:

  • Overall: Arrests involving bench warrants were relatively common in both cities, accounting for approximately one-third of arrests in 2019.
    • In St. Louis, for example, 14% of arrests in 2019 were for bench warrants (with no new charge), and 39% of arrests involved at least one bench warrant.
    • In Louisville, arrests for bench warrants (with no new charge) accounted for 19% of all arrests, and there was at least one bench warrant in 34% of all arrests.
  • Variance across jurisdictions: Between 2006 and 2019, arrest rates involving bench warrants without new charges followed different trends in the two cities, with declines recorded in St. Louis and increases in Louisville.
    • In St. Louis, the arrest rates based on bench warrants (with no new charge) decreased 59% between 2006 and 2019 – with much of the reduction occurring after municipal court reforms were enacted.
    • In Louisville, the arrest rate based on bench warrants (with no new charge) increased by 73% during the same period.
  • Racial disparities: In both cities, racial disparities in arrests made solely on the basis of bench warrants narrowed over time but were still present in 2019.
    • In St. Louis, in 2006, there were almost seven Black people arrested for a bench warrant without a new charge for every White person arrested. In 2019, this ratio was just over four-to-one.
    • In Louisville, in 2006, there were almost four Black people arrested for a bench warrant without a new charge for every White person arrested. In 2019, this ratio was closer to three-to-one.
  • Warrants by charge type: In both cities, most arrests made based solely on bench warrants without new charges were frequently associated with ordinance violations or misdemeanors.
    • In St. Louis, 53% of 2019 bench warrants arrests (with no new charge) involved a municipal violation and 13% involved misdemeanors.
    • In Louisville, 13% of 2019 bench warrants arrests (with no new charge) involved a municipal violation and 42% involved misdemeanors.
    • In both cities, for people who were arrested and had an open bench warrant, a traffic violation (e.g., driving on a suspended license or without valid insurance or registration) was the most common type of charge underlying the bench warrant.
    • In St. Louis, for Black people arrested in 2019, almost three-quarters of their bench warrants stemmed from traffic offenses and among White individuals, more than half were linked to this type of violation.
    • In Louisville, the percentages were lower, but traffic violations were still the most prevalent charge type, and a higher percentage of bench warrants originated with traffic violations for Black people (37%) than White individuals (25%).
  • Arrest Involving Fugitive Warrants: Arrests tied to fugitive warrants were prevalent in St. Louis but rare in Louisville. More than one-third of the arrests made by the St. Louis Metropolitan Police Department in 2019 (38%) involved people with a fugitive warrant (warrants that had been issued by a court in another municipality) compared to less than 3% in Louisville.
    • In St. Louis, 10% of 2019 arrests were based solely on a “fugitive warrant” (no new charge).  This is likely explained in large part by the fragmented nature of governance and criminal justice enforcement in St. Louis County which is comprised of 88 distinct municipalities – many with their own police forces and municipal courts. Due to the high number of municipal courts and law enforcement agencies operating in the region, people may regularly move through different municipalities, be charged in multiple municipalities (e.g., on driving related charges), and have outstanding warrants in multiple municipalities.  When this occurs, people may be required to settle warrants separately in each court.