The investigation used jail booking data to track the race and gender of every person charged with “Possession With Intent to Distribute Marijuana” in Greenville County over a period of several years. Then they used court records and law enforcement FOIAs to track the location of each arrest. Finally they used census data to understand the demographic composition of each neighborhood in the county. When they were finished, they'd found that black people were arrested for PWID at a far higher rate than white people, neighborhoods with the most black people saw far more arrests, and the rate of black people charged was disproportionate with the demographics in each area. They further established that black and white people use and sell the drug at similar rates meaning the discrepancy with arrests was due to differences in enforcement policy.