In a case that spanned more than half a century, the Felix Vail Murder conviction finally brought accountability for the 1962 killing of Mary Horton Vail. Nearly 54 years ago, Mary’s body was pulled from the dark waters of Louisiana’s Calcasieu River.
In 2016, a jury found her husband, Felix Vail, guilty of the murder and rejected his long-held claims that her death was an accidental drowning.
A Cold Case Murder That Refused to Die
The Felix Vail Murder case is now recognized as the oldest prosecution of a suspected serial killer in U.S. history. Mary Horton Vail was just 22 years old when she died in August 1962 while reportedly fishing with her husband. Felix Vail told deputies she fell from the boat while they were checking trotlines.
That explanation held for decades. But investigators, family members, and later prosecutors never stopped questioning how a young woman could drown under such suspicious circumstances—especially given what followed in Vail’s life.

