"Any man who can hold his daughter down and rape her is evil," she said. "And nobody stopped him. No one." That included Lannert's baby sitter, who confirmed to ABC News that she suspected abuse when Lannert was 12.
Lannert's mother, Deb Underwood, said she was unaware of what was happening to her daughters before and after her divorce. Otherwise, she would never have left them with their father.
"What I felt was that he loved them and he would not hurt them. I thought he loved his daughters," she said. "I feel like I failed to protect my children … and I will never ever forget that. I will never live this down no matter what."
McCulloch said that's not a believable statement.
"He was not Ozzie Nelson, no. He was a bad father," McCulloch said. "He was a bad parent, and he was a bad drunk. But there is no evidence that he was sexually abusing. You know you can be a rotten SOB and still not be a rapist."
McCulloch said Lannert is lying "through her teeth."
"The only credible evidence of any sort of motive is that she did it for the money," McCulloch said. "And she's not going to get her hands on it unless she -- unless she takes out her father."
McCulloch wondered why if things were so bad, Lannert didn't just leave.
But she had tried. Six months before the murder she went to live with her mother 7,000 miles away, on the Island of Guam, only to return home after a desperate call from Christy.
"All I really cared about was making sure that Christy never had to go through that pain that I had to go through, ever. I never wanted that for her," Lannert said.
She said she begged her father to let her take her sister away, but he told her no.
"All he wanted her for was to control me," she said.
One month later, Lannert shot her father and confessed to Lt. Tom Schulte, telling him that the years of abuse had led to the murder.
Schulte remembered, "The last thing that I told that young lady when I left her -- and it was late that night, I told her, 'I'll be there for you.'"
But the prosecutor didn't call him to testify, even though Schulte had spent years investigating child sex crimes, and he was the first person to question Lannert.
"I didn't fit in with the focus of the prosecution at that time," Schulte said, adding that the prosecutor was hungry for a first degree murder conviction. For years, Lannert felt frustrated and betrayed because Schulte hadn't testified. It wasn't until recently that she learned he would have testified on her behalf had he been called to the witness stand.
Schulte purposefully refrained from contacting Lannert while she was in prison. He didn't want his affidavit to be colored by anything other than his observations on the night he had questioned her.
After first suggesting that a burglar had murdered her father, Lannert ended up confessing on video as Schulte asked her to guide him through the crime scene.
She told police that she and her father had argued earlier in the day. When her two sisters came home very late they crawled through the basement window, hoping he was asleep and afraid he was drunk. They often sneaked into the house this way.
But Christy accidentally woke their father, and Lannert said her sister and father started yelling at each other.
"What's in my head is that we're leaving. We're leaving, and if you try to stop us I'm going to kill you. That's what's in my head," she told McFadden.