The convicted killer who says he was sleepwalking when he brutally murdered his wife 24 years ago is speaking out behind bars. In Jan. 1997, Scott Falater stabbed his wife 44 times before drowning her in the pool.

When Phoenix cops arrived on the scene, they found Falater in his pajamas at the top of the stairs, appearing to have no memory of what happened. The case made headlines due to his sleepwalking defense, and Inside Edition was in the courtroom when he was sentenced to life without parole.

Now, 22 years later, Falater still says he still doesn’t remember committing the crime. In a 20/20 special airing Friday, Falater spoke to ABC’s Amy Robach.

“I think about what she had to go through that night, and the pain and the terror she had to feel. I can’t even fathom. But I believe she would be willing to be more understanding and forgiving of me than I feel about myself, yes,” Falater said.

His son Michael was just 12 years old at the time of the murder.

“In the 20 plus years since I lost my mom, I think about her everyday. I think about what she could be doing with my kids now. What life could have been like, and things that I have missed out on,” Michael says in the upcoming special.