After an eight-day trial and 25 hours of deliberation, a jury convicted Jack Callahan of involuntary manslaughter in the death of his father, Scott Callahan. According to prosecutors, the younger Callahan had picked up his father from a treatment center for alcohol abuse and drove him to a pond in Duxbury. An altercation occurred between the two, and the son submerged his father’s head in the water multiple times. Despite attempts by authorities to resuscitate Scott Callahan, he was pronounced dead at a nearby hospital. The medical examiner determined that the cause of death was drowning, and the manner of death was homicide. Jack Callahan initially pleaded not guilty to murder charges but was convicted of the lesser charge of involuntary manslaughter. He is scheduled to be sentenced on May 3.