About the database

To collect data for pursuits of human smugglers that the Border Patrol engaged in from 2015 to 2018, reporters from ProPublica and the Los Angeles Times reviewed more than 9,000 documents related to prosecutions under the charge “bringing in and harboring aliens” in the five federal court districts along the U.S.-Mexico border: Arizona, South Texas, West Texas, Southern California and New Mexico.

Reporters determined whether a pursuit had taken place by applying the definition used by the California Commission on Peace Officer Standards and Training and the California Highway Patrol: “An event involving one or more law enforcement officers attempting to apprehend a suspected or actual violator of the law in a motor vehicle while the driver is using evasive tactics, such as high-speed driving, driving off a highway, turning suddenly, or driving in a legal manner, but failing to yield to the officer’s signal to stop.”

Most pursuits involved a Border Patrol agent in a marked vehicle attempting to conduct a stop and then pursuing that vehicle after it failed to yield. In a few cases, agents did not note whether they had activated their lights and sirens, but followed vehicles after they began making evasive maneuvers or driving well above the speed limit. Agents were often driving at speeds close to 100 mph.

The database relies only on court documents to come to conclusions about increases in prosecutions, pursuits, crashes and the use of tactics.

The number of injuries is likely an undercount. Even in high-speed crashes in which agents found blood inside a vehicle, reporters did not count injuries unless the number was specifically noted in a news report or document.