Nearly five years after Todd Sommer's death, his wife Cynthia was convicted of murdering her Marine Sergeant husband with a lethal dose of arsenic. But ten months after her conviction, she was granted a new trial due to decisions the defense made that deprived her of a fair trial. Then questions arose about the validity of the lab tests. Would this be enough to exonerate her? “48 Hours" correspondent Richard Schlesinger reports. This classic "48 Hours" episode last aired on 4/24/2010. Watch all-new episodes of “48 Hours” on Saturdays, and stream on demand on Paramount+.