Washington -- A Prince George's County, Md., jury would not convict a man accused of stabbing his girlfriend to death because a half-eaten hamburger, recovered from the crime scene and assumed to have been his, was not tested for DNA. In Washington, a jury deadlocked recently in the trial of a woman accused of stabbing another woman because fingerprints on the weapon did not belong to the suspect. An Alexandria, Va., jury acquitted a man on drug-possession charges in part because a box containing 60 rocks of crack cocaine that he was accused of tossing from his car during a...