On April 9, 2009, Hackett, acting as defense counsel to Sgt. Ryan Weemer, USMC, obtained an acquittal on charges of murdering an insurgent in Fallujah on November 9, 2004, the Second Battle of Fallujah's first day. Weemer had contacted Hackett two years earlier after he had successfully represented other Marines charged with violations of the law of war in Haditha in November 2005. Hackett represented Weemer pro bono. When asked why, Hackett stated that "these Marines protected me when I was in Fallujah, it's the least I could do." The trial lasted two weeks after which the 8 member court martial deliberated for 8 hours and announced its decision acquitting Weemer of all charges and specifications, to unpremeditated murder and dereliction of duty. Weemer's acquittal was awarded by the 8 member jury despite the government's introduction into evidence of Weemer's audio confession to the alleged violations of war. Despite the audio confession, the 8 member jury was persuaded by Hackett's argument and through his cross examination of NCIS Special Agent Fox that Weemer had been coerced into confessing to the charged offenses by his interrogators; namely NCIS Special Agent Fox.