About the Data

This analysis uses defendant-by-defendant data from the U.S. Department of Justice obtained under the Freedom of Information Act. These data are kept by each of the assistant U.S. attorneys in the 94 U.S. Attorney Offices around the United States and its territories. The Executive Office for United States Attorneys requires prosecutors to record information about their handling of every matter they receive from investigative agencies such as the FBI, DEA, ATF, and the DHS's Customs and Border Protection (CBP) and Immigration and Customs Enforcement (ICE). Over 500,000 cases covering FY 2007 through FY 2010 were analyzed. Additional data on full-time federal employees came from the Office of Personnel Management. Bureau of Census population figures were also used in the analysis to adjust for population differences among federal districts.

Focus on Felony Prosecutions. There are thousands of different statutes that are the responsibility of federal prosecutors to handle — varying from traffic offenses on federal parkways and military reservations to much more serious offenses. The same defendant can be charged with multiple offenses ranging in their seriousness level.

Historically, EOUSA has reported on the prosecutions filed by each U.S. Attorney Office in its annual reports but has not published breakdowns that separate out prosecutions by the seriousness of the charge — e.g. for felonies versus less serious misdemeanors and petty offenses. This at times can result in somewhat misleading statistics since one district may have a larger number of prosecutions filed because of a high volume of fairly minor offenses.

This report breaks new ground by focusing on felony prosecutions. It also includes prosecutions whether initially filed in U.S. magistrate or district courts so long as at least one of the charges was a felony. Because of differing practices among federal districts, the same set of charges might be initially brought in a district court in one district but would be filed in a magistrate court in another. Over time the role of magistrate judges in many federal districts has grown. Thus, selecting cases by whether or not a felony is charged — rather than by the type of court — helps to ensure more uniformity in treatment of similar cases over time and from one district to the next.

It is common to charge a defendant with multiple counts — some involving lesser charges. The case was counted as a conviction if the defendant was convicted on any of the charges.

Type of Case. A long-standing aspect of the EOUSA database system requires the assistant U.S. attorney to determine the "program category" — white collar crime, immigration, civil rights, official corruption, etc. — for each matter. Assistant U.S. attorneys need not limit their assignment to a single program category, but can assign as many programs as they believe relevant to the same case. This report classifies a case as an "immigration" prosecution if federal prosecutors classified it under the immigration program category. It does not require that immigration be the sole assignment. (This contrasts with EOUSA when tabulating prosecutions by program where multiple assignments are ignored. While this greatly simplifies tabulating cases by avoiding multiple assignments, selection of the single category from multiple assignments can be somewhat arbitrary since prosecutors do not designate any one program as primary.)

While there are general guidelines for the assignment of program categories, the assignment is essentially based upon the subjective judgment of each assistant U.S. attorney. TRAC found that the vast majority of cases with an immigration-type lead charge were classified as an immigration program case. But this did not always occur. On those occasions TRAC also treated the case as an immigration prosecution if the lead charge was a Title 8 charge such as illegal entry, illegal re-entry or a Title 18 charge involving misuse or fraud with visas, passports, and other immigration documents.

A non-immigration prosecution covered any other type of prosecution.

Geographic classification. Federal prosecutions are filed in one of 94 federal judicial districts, and separate comparisons were made for each district. Five out of the 94 districts lie along the U.S. border with Mexico: Arizona, Southern District of California (San Diego), New Mexico, Western District of Texas (San Antonio), Southern District of Texas (Houston). These five districts are referred to as the "southwest border" districts, while the remaining 89 districts are grouped together as the "rest of the nation."

Time period selected. President Obama has been in office now for two years. We have used the last two fiscal years — FY 2009 and FY 2010 — to approximate this time in office, and compared it with the last two years of the Bush administration — FY 2007 and FY 2008. While this makes it easier to compare counts since we have exactly two years in each comparison period, the selection also has its limitations. A fiscal year begins on October 1, rather than on the actual date that President Obama assumed office. In addition, at the point of a change in presidency there is an existing workload in each U.S. attorney's office that reflects investigations and referrals that took place during the previous administration. Further, there is usually some delay before new U.S. attorneys are appointed by the new President and can assume office.

Accordingly, for tables at the national level we have presented figures for each of the four years separately so that any anomalies present for FY 2009 can be seen and actual trends, where present, can be more readily discerned. However, we have grouped years in the two tables presenting district-by-district comparisons because of the much smaller volume of cases present in individual districts. Two-year comparisons help smooth out inevitable year-to-year fluctuations that would occur even in the absence of any change in presidents. To the extent there was an actual change in priorities between the Bush and Obama administrations for a given district, resulting comparisons will give more conservative estimates for such trends.