The trial of a former medical examiner accused of staging a bizarre bomb attack against himself ended Tuesday in a hung jury. U.S. District Judge Bernice Donald declared a mistrial after the jury spent about 2½ days deliberating in the case of Dr. O. C. Smith. In 2002, Smith was found in the county morgue stairwell with his feet, hands and face wrapped in barbed wire and a motion-sensitive bomb around his neck. Smith told authorities he was attacked by someone who threw a caustic chemical in his face. Investigators initially suspected a death penalty opponent had attacked Smith, then Shelby County's medical examiner. About a year later, they filed charges accusing Smith of staging the attack. He was charged with lying to investigators and illegal possession of a bomb. Federal prosecutor Bud Cummins said the government will probably decide in the next few weeks whether to retry Smith. Prosecution witnesses included medical personnel who said Smith's injuries were not consistent with his description of the attack and a forensic psychiatrist who testified that false crime reports can be symptoms of a mental disorder. The defense contended that prosecutors did not fully explain how Smith could have staged the attack alone. Smith could have gotten 20 years in prison on the charges. The government brought in Cummins, the U.S. attorney in Little Rock, Ark., after local authorities stepped aside because they had worked with Smith on other cases.