The US public has a constitutional right to access criminal trial proceedings. In practice, it is difficult to exercise this right as well as to quantitatively study federal sentencing disparities. We have assembled a public database of criminal sentence decisions made in federal district courts called JUSTFAIR: Judicial System Transparency through Federal Archive Inferred Records. This large-scale database links information about defendants with information about their federal crimes and sentences, and, crucially, with the identity of the sentencing judge. In this talk, we discuss challenges associated with assembling this database as well as preliminary work and observations from studying sentencing equity and patterns of individual judges.