William George Davis (born February 3, 1984) is an American serial killer and former nurse.
He was convicted of capital murder for killing four patients with air injections after they received heart surgery at Christus Trinity Mother Frances Hospital in Tyler, Texas.
Davis was discovered after doctors observed air in the brains of patients on CT scans.
Prosecutors pushed for the death penalty and played a recording of a call from Davis in jail to his ex-wife in which he claimed that he wanted to lengthen the patients' time in the intensive care unit so that he could earn more overtime.
[4][5] Davis was convicted of killing John Lafferty, Ronald Clark, Christopher Greenaway, and Joseph Kalina.