Police rushed to Daniel Kerrigan's Stoneham, Mass., home on Jan. 25, 2010 after Kerrigan's wife, Brenda, called 911 and reported that her husband had fallen.
But during the call, Brenda Kerrigan could be heard yelling for her son, Mark, to get away from her husband.
Asked by the 911 operator whether there was fighting in the background, Brenda Kerrigan said: "Oh, yes."
Her son then took the phone and spoke to the operator himself, telling the operator that his father had fallen down.
"He seemed to have a heart attack," he said.
Prosecutors say that heart attack may have been provoked by the physical altercation with his son.
Emergency responders took Daniel Kerrigan to nearby Winchester Hospital, where he was pronounced dead.
Elizabeth Keeley, the assistant district attorney, outlined the case against Mark Kerrigan.
"Daniel Kerrigan spent the last few minutes of his conscious life fending off his drunk 45-year-old son," Keeley said.
According to authorities, the altercation between Mark Kerrigan and his father stemmed from a disagreement over using the phone to contact a woman.
Mark Kerrigan allegedly became angrier and more aggressive and continued to drink alcohol and argue with his father when he was refused access to the telephone. Several hours later, Mark Kerrigan allegedly attacked his father.
Authorities determined that Daniel Kerrigan suffered a compression fracture to his left thyroid cartilage of his larynx which eventually led to his death, but the Kerrigan family has said that they believe the death was a result of a heart condition, and not the altercation with Mark Kerrigan.
Janice Bassil, Kerrigan's defense attorney, said her client loved his father.
"He didn't kill him. Daniel Kerrigan was a very, very sick man -- no one knew it -- maybe he knew it, but he didn't share it with anybody," she said.
Brenda and Nancy Kerrigan had no comment for reporters as they went into the court. Prosecutors could call both women to the stand to testify.
Nancy Kerrigan, 41, of Lynnfield, Mass., won the bronze medal at the 1992 Olympics in Albertville, France.
In 1994, she was the victim of an attack in which her assailant struck her in the knee during practice for an upcoming competition.
The assailant was the ex-husband of rival figure skater, Tonya Harding, and Harding was implicated in the crime.
Kerrigan recovered and went on to compete in the 1994 Winter Olympics in Lillehammer, Norway. She won a silver medal.
ABC News' Emily Friedman contributed to this report.