The comparisons of the number of defendants charged are based on case-by-case information obtained by TRAC under the Freedom of Information Act from the Executive Office for United States Attorneys (see Table 1).

These data suggest that at least through the first five months of the Obama Administration there has been no let up in the increase in criminal prosecutions as a result of ICE's enforcement activities. When monthly 2009 prosecutions in May are compared with those of the same period in the previous year, the number of filings was up 29.8 percent.

ICE is the largest investigative agency within the Department of Homeland Security. Other key units in DHS include the Border Patrol (BP), the Transportation and Security Administration (TSA), Secret Service (SS) and United States Citizenship and Immigration Services (USCIS).

Figure 1: ICE Criminal Prosecutions Over Time

The increase in prosecutions for these matters is shown more clearly in Figure 1. The vertical bars in Figure 1 represent the number of prosecutions of this type recorded on a month-to-month basis. The superimposed line on the bars plots the six-month moving average so that natural fluctuations are smoothed out. This moving average also provides the basis for the one-year change identified in Table 1.

The majority of the prosecutions filed during May were for immigration offenses (55%), while one third (33%) were for drug offenses. However, none were recorded as brought against employers under the statute 8 U.S.C. 1324(a)(3)(A), which makes it a criminal offense to knowingly hire illegal aliens.

Top Ranked Judicial Districts

Arizona has jumped to the top as the district with the largest number of prosecutions resulting from ICE enforcement activity during May 2009. In that district 314 prosecutions were filed. It was followed closely by the Western District of Texas (San Antonio) with 303 new prosecutions, the Southern District of California (San Diego) with 293, the Southern District of Texas (Houston) with 237. The District of New Mexico rounded out the top five with 100 new prosecutions during May.

While the heaviest concentration of cases was centered in districts along the southwest border, ICE enforcement actions have become widespread throughout the country. In fact, during the single month of May, fully 80 out of the total of 90 federal districts saw one or more prosecutions that had resulted from ICE enforcement actions. Looking at a three month window — March through May of 2009 — at least one ICE-referred case had been filed in every district.

Table 2 lists prosecutions due to ICE activity for those federal judicial districts that ranked in the top third in May 2009. Also shown are the number of prosecutions for the United States as a whole, as well as the numbers for each district for the first five months of the Obama administration.