John Lausch, who spent five years as the U.S. Attorney for the Northern District of Illinois before stepping down, is returning to Kirkland & Ellis as a partner in its government, regulatory and internal investigations practice group. Lausch started his legal career at the firm in 1997 before leaving in 1999 to become an assistant United States attorney in the Northern District of Illinois.At Kirkland, Lausch’s practice will focus on government enforcement defense, internal investigations and other litigation …