On November 3, 2005, it was announced that Lawton had tested positive for performance-enhancing drugs. This led to a 10-day suspension by MLB. As a free agent at the time, Lawton was to serve his suspension at the start of the 2006 regular season. The test was taken after Lawton's acquisition by the New York Yankees in August 2005. The specific drug he was suspended for was the veterinary steroid boldenone. Lawton made the following statement to the Associated Press following his suspension: