He was United States Attorney for the Western District of Wisconsin during the presidency of Barack Obama.

In 1992, he was designated as a Senior Litigation Counsel by the Department of Justice, and in June 2002 he was named the Chief for the Criminal Division for the United States Attorney's Office.

Since 1992, he has taught thousands of U.S. prosecutors regarding evidence, trial advocacy, and criminal procedure.

Since 2001 he has supported the rule of law efforts of the U.S. Department of Justice, teaching prosecutors, defense attorneys, and judges in many foreign countries.

[3] This article incorporates public domain material from websites or documents of the United States Department of Justice.