Markham Duff-Smith

Age: 46

Summary: convicted murderer accused of being the mastermind behind a murder-for-inheritance scheme in which four people were killed who was convicted of paying $10,000 to another man Allen Janecka (who is also on death row) to murder his wealthy adopted mother Gertrude Duff-Smith Zabolio at her home in the exclusive River Oaks neighborhood of Houston, Texas in 1975 so he could inherit the family fortune, who was indicted but never tried for the shooting deaths of his adoptive sister Diana Wanstrath, her husband John, and their 14-month-old son Kevin in a similar scheme in 1979.

Cause of Death: Executed by lethal injection

Born: January 14, 1947

Died: June 29, 1993

Location: Huntsville, Texas