To give the jurors a sense of what life was like in the Beard house, the prosecution plays a recording of a telephone conversation between Celeste and Kristina.
Celeste on audio tape: "You'd better get your ass home tonight."
Kristina says she recorded it in hopes of one day playing it back to Celeste, so she'd understand how verbally abusive she could be.
Celeste on audiotape, screaming, before dropping the phone and wailing in the background: "And I'm sorry that I have all of these mental problems. Just as soon as I get home, I feel like just ... sticking a knife down my throat..."
"It's real clear who the emotionally abusive one is," says Weitzel. "And who the bad guy in the relationship is. And it's not these girls."
"There's no excuse for what I did, and I'm sorry that I talked to my daughter that way," says Celeste about her recorded conversation with Kristina. "I used to say if I didn't cuss her out and didn't talk to her like that, then I wouldn't be sitting here."
DeGuerin, Celeste's attorney, decides not to put his client on the stand. But he brings in some of her friends.
"Steve definitely loved Celeste, and Celeste definitely loved Steve," says friend Dawn Maddigan. "They were kind to each other and devoted."
DeGuerin also calls three mental health experts to the stand who had been involved with Tracey at various psychiatric facilities. They say Tracey's mental problems are so severe, she could have imagined, even fabricated, a romantic relationship with Celeste.
Dr. Howard Miller: "Tracey had a need to believe that Celeste was the one who loved her. She clearly persisted in a delusional belief."
After more than one month of testimony, both sides present their final arguments.
"Was she in a relationship with Tracey Tarlton? And did that relationship lead to Tracey Tarlton, at Celeste Beard's encouragement, to shoot Steven Beard," asks co-prosecutor Gary Cobb. "I think the evidence is overwhelming on that."
Cobb also says that Celeste wanted Steven dead because she would inherit millions. A divorce would have been an entirely different financial picture.
"I'm going to show it to you right now. Here, it is right here," says Cobb, turning a giant placard over, revealing a blank side. "On the back. Look closely. She would have had a big pocket full of empty."
Weitzel, lead prosecutor, summed it all up. "Folks, if you say that Celeste Beard is not guilty, with all of this evidence, then you're going to tell her that her money can buy anything."
"This soap opera that we went through for four weeks does not prove Celeste is a killer," says DeGuerin, who tells the jury that money had nothing to do with Steven Beard's murder.
Rather, he argues, it was one woman's obsession. "Tracey Tarlton killed Steven Beard on her own, for her own selfish reasons, for her own sick reasons. The only evidence they have is Tracey Tarlton. And Tracey Tarlton can't be believed, because she's a crazy woman."
"Should I be believed because of my mental health," asks Tracey. "I don't know about that. You know? All I know is that I'm telling you the truth."
"They have not proven Celeste Beard guilty because they have not corroborated the unbelievable testimony of Tracey Tarlton," says DeGuerin.
But who will the jury believe?
After two-and-a-half days of deliberation, the jury has decided Celeste Beard's fate.
"We the jury find the defendant, Celeste Beard Johnson, guilty of the offense of capital murder."
"My life is over. I'm devastated," says Celeste, crying. "I'm scared. I'm terrified. I don't want to go to prison. I don't want to be with people that have actually murdered somebody."
DeGuerin, walking out of courtroom, says, "We're all very, very disappointed. We believe sincerely in Celeste's innocence. We believe this conviction is wrong."
The next day, before Celeste is sentenced, her daughter Kristina takes the stand and speaks directly to her mother for the first time in nearly three years.
"What did I ever do to you, or Jenn, except love you? And this is how you treated us, like trash. We'll go on. Everybody will get to go home but you," says Kristina.
"You say we turned on you. Well, you turned on us. You turned on the whole Beard family. He let you into his home, loved you, honored, obeyed you, and you violated him and murdered him. You are guilty. Time will heal all wounds, and of course, we will all go on," adds Kristina, choking up in tears. "Shame on you!"
It was now time for Celeste to receive her sentence. The prosecution had agreed to not seek the death penalty. She was sentenced to life in prison.
Celeste lost her husband, her home, and now her freedom. "And I've lost my children," says Celeste, crying. "I bear responsibility, and I feel responsible in the fact that I brought Tracey into our lives."
"But am I responsible for Tracey going into the house and shooting Steven? No, I'm not responsible for that."
Celeste Beard's lawyers are appealing her conviction.
Texas law makes it almost impossible for Celeste to collect any inheritance. In the year since 48 Hours first aired this broadcast, the future of Steve Beard's $10 million estate has remained unsettled. But it's likely to be divided among the twins and his three children from a previous marriage.
Celeste has no chance of parole until she serves 40 years of her life sentence. By then, she'd be 80. As for Tracey Tarlton, who pulled the trigger and turned state's evidence, she's eligible for parole after doing 10 years of her 20-year prison term.