Methodology for TRAC's judge tool and AP analysis

The data and the new interactive judge tool were developed by the Transactional Records Access Clearinghouse at Syracuse University over 15 years of research. Data were obtained under the Freedom of Information Act in a series of four lawsuits against the Justice Department, and then combined with information obtained directly from the federal courts. The data cover sentences imposed by federal district court judges during the past five budget years, 2007-2011.

In a special analysis conducted by TRAC at the request of The Associated Press, federal district court judges were divided into those appointed by Republican versus Democratic presidents to compute their average sentences after trials.

Sentences imposed after guilty pleas without trial were excluded, even though they constitute more than 90 percent of convictions in federal courts. That was because these are usually the result of plea bargains between defendants and prosecutors for reduced sentences over which prosecutors exercise outsized influence compared to judges, who almost always accept these deals.

Separate analyses were carried out for three most common types of charges — drug, weapons, and white collar. The top 10 districts represent those with the most trials by judges appointed by each party.

In the case of white-collar crime cases, a smaller number of trials left only seven districts that met a minimum standard of at least 20 trials for judges appointed from each party.

In computing these averages, prison terms were capped at 100 years to avoid the undue influence of an extreme sentence. A value of zero was used for sentences in which no prison time was imposed and life sentences were valued at 100 years.

TRAC's overall database includes all judges who sentenced at least 50 defendants over the past 5 years, whether after trial or plea. This included 882 judges appointed by presidents from John Kennedy through Barack Obama — 355 appointed by Democratic presidents and 527 by Republicans. During that time, more than 370,000 defendants were sentenced by these judges, for an average of 420 defendants sentenced per judge over the five years.