Blanchard then became a law clerk to Judge Harry T. Edwards of the United States Court of Appeals for the District of Columbia Circuit (1985-1986) and Justice Sandra Day O'Connor of the Supreme Court of the United States (1986-1987).
Blanchard left Brown and Bain in 1997 to become Chief Legal Counsel of the Office of National Drug Control Policy.
In 1999, President of the United States Bill Clinton nominated him to be General Counsel of the Army and he subsequently held that office from 1999 to 2001.
In 2009, President Barack Obama nominated him to be General Counsel of the Air Force and he held that office from 2009 to 2013.
Subsequently, Blanchard joined the law firm Arnold & Porter working in their government contracts and national security groups.