The case gained national attention, leading up to the 1979 conviction of Jeffrey MacDonald, a former Army doctor with the elite Green Berets.
Imprisoned for the past 25 years, MacDonald has never waivered from his claims of innocence.
Correspondent Bill Lagattuta reports.
"Prison is difficult for everyone. It's very difficult for the guilty, and it's very difficult for the innocent," says Dr. Jeffrey MacDonald.
"Innocent" is a word tossed around a lot behind prison walls, but for inmate MacDonald it's the only word that has ever mattered.
"My focus for all these years has been to prove my factual innocence, and walk out of prison with my head held up," says MacDonald, 61. He has desperately held on to that goal since 1979, when he was convicted of one of the most notorious murders in recent history.
Jeffrey MacDonald had a bright future. He made his mark early on in high school when he was voted most likely to succeed. He went to Princeton University, and Northwestern Medical School. At age 25, he got a captain's commission as a doctor in the Army's elite Green Berets.
Along the way, MacDonald managed to capture the heart of his high school girlfriend, Colette Stevenson, and they were married while he was still at Princeton.
During the next seven years, as their family grew, it appeared that the MacDonalds were well on their way to a seemingly perfect life.
But in 1970, life in America was far from perfect.
"This was an era of shock and counterculture rage in America," says Bernard Segal, a law school professor who, at the time, was MacDonald's defense attorney. "I was a lawyer for people who felt they were not represented by the system and who were outside the system."
MacDonald though, was, in fact, deep inside the system. Jeffrey, Colette and their daughters Kimberley, age 5, and Kristin, age 2, were stationed at the largest military base in the country, Ft. Bragg in Fayetteville, N.C.
The happy times at Fort Bragg ended during the early morning hours of Feb. 17, 1970.
What happened in the MacDonald house that night is one of America's most enduring murder mysteries, the subject of a best-selling book, a sensational TV movie, and a mysterious story kept alive by its charismatic leading man, Dr. Jeffrey MacDonald.
Army MPs arrived at the MacDonald home, responding to a call for help, and found the couple's children dead in their bedrooms. Jeffrey MacDonald was found wounded and unconscious, beside the body of his dead wife.
"I realized someone was breathing in my mouth. And I opened my eyes, and I could see a ring of military police helmets circling me," MacDonald says.
He was taken to the hospital, where a colleague told him his family had been murdered. "You can't accept something like that. It doesn't make any sense," says MacDonald.
In fact, that morning MacDonald wasn't the only one having trouble making sense of what happened.
"My gut told me that what he told the investigators and what he told the military police, could not possibly have happened in that house," says Bill Ivory, who was a criminal investigator for the Army and in charge of the crime scene.
Ivory says MacDonald told his agents at the hospital that he had been attacked by some hippies. It is a story that MacDonald has told again and again, for the past 35 years.
MacDonald says he remembers seeing four people, including two white men, a black man and what he thinks was a blonde woman wearing a floppy hat.
"I heard a female voice say, 'Acid is groovy, kill the pigs.' I heard that several times," says MacDonald. "There became a moment in time where all I was doing was fending off blows with both my hands wrapped up in my pajama top. I suddenly had a chest pain. The right side of my chest hurt."
MacDonald had been stabbed in the center of his chest with an ice pick, puncturing his skin and the layers below.
But the attack on his family was considerably more vicious as revealed by their autopsies. Colette suffered two broken arms, a fractured skull and was stabbed more than 30 times. Five-year-old Kimberley's skull, jaw and nose were badly broken and her throat was severely cut. And Kristen, just 2½ years old, was stabbed repeatedly in her chest and back.
The autopsy also revealed one last devastating detail: Colette was five and half months pregnant with a son.
MacDonald tells a very compelling story of what happened that night but there are others who say the evidence found in the apartment says something very different.