William Stevenson, who was married to Jill Biden from 1970 to 1975, pleaded not guilty Tuesday in his wife's death in Delaware. Stevenson attended a court hearing remotely on Tuesday after he was charged earlier this month with killing Linda Stevenson. His 64-year-old wife was found unresponsive at their home in Wilmington on Dec. 28. Stevenson is set to appear in court again on March 16. #delaware #wilmington #wilmingtonde