Twenty-seven percent (27%) of all arrests by the U.S. Marshals service were for immigration offenses in 2005, the latest year from which data was available. Immigration arrests rose nearly 15% in the decade from 1995-2005.
By comparison, drug arrests accounted for 24% of the total, growing at just three percent over the decade.
The increase in immigration arrests can also be seen in the geographic breakdown of the Bureau of Justice Statistics report: Of the 93 federal judicial districts, just five districts along the U.S.-Mexico border in the Southwest accounted for 40% of all the federal apprehensions. Nearly a quarter of all bookings came in the Southern and Western districts of Texas.
For the suspects detained on immigration charges in 2005 who fought the law, the law won—at a much higher rate than drug or violent offenders. Over 95% of the immigration cases ended with a guilty plea or conviction.
The full report is available at http://www.ojp.usdoj.gov/bjs/abstract/fjs05.htm