Authorities had previously described Joseph James Pappas as armed, dangerous and possibly suicidal HOUSTON: Houston’s police chief says a man accused of killing one of former President George H.W. Bush’s doctors has killed himself. Chief Art Acevedo made the announcement at a news conference Friday. Police allege Pappas shot Dr. Mark Hausknecht on July 20 while the cardiologist rode his bike to work at Houston Methodist Hospital. Acevedo has said Pappas might have been seeking revenge for his mother, who died on the doctor’s operating table more than 20 years ago, in April 1997. Authorities had previously described Joseph James Pappas as armed, dangerous and possibly suicidal.