Transcript for Podcasters push innocence of ‘Suitcase Killer’ Melanie McGuire
We turn now to new developments and a murder case that made headlines. Melanie Mcguire was convicted of the gruesome murder of her husband and sentenced and life in prison. Amy talks about it on "20/20" tonight. She has a preview now. Reporter: Melanie Mcguire became known as the suitcase killer and her guilt is being questioned by two professors who believe she was wrongly convicted. This is Melanie Mcguire, arrested minutes after dropping her children off at day care. Reporter: The case of Melanie Mcguire, convicted in 2007 of shooting and dismembering her 39-year-old husband, bill. Melanie Mcguire might as well have taken out a billboard on 3rd avenue that said, I murdered my husband and hacked his body up. Reporter: It's get a fresh look thanks to a new podcast launched by criminal professors. I started thinking, oh. Maybe there is a little more to this case than what you just see on the surface. On direct appeal, we examined the murder conviction of Melanie Mcguire following the highly publicized trial. She had done poorly in the court system, and I think she was frustrated. After visiting with her the first time, I was, like, this is a story. This is important. It was very difficult. It was reliving it. This was the first time somebody was basically saying, we hear you. Reporter: One of the most damning pieces of evidence against Mcguire was the fact that just two days before her husband went missing, she purchased a gun. Is it possible that the gun Melanie bought is not actually the murder weapon? I think it's probable. No one plugged serial number of my gun into a website to find out what the specifications were. Apparently each gun makes something called lands and grooves. When the bullet passes through the barrel, the same number of lands and grooves will be imprinted. There were five that my weapon was said to have made based on the company's website. That bullet that came out of my husband had six lands and grooves. It was a mistake on a gun manufacturer's website. Reporter: Patty is the woman who prosecuted Melanie Mcguire. The evidence that was at trial was from ballistic experts. As I sit here right now, I am absolutely certain that the person who's most responsible for bill Mcguire's murder is in jail right now, and that's Melanie Mcguire. Now we are reexamining this entire case file tonight on "20/20." I sat down with Melanie Mcguire for her first on-camera interview since her conviction behind bars as well as the lead investigator and prosecutor who both believe the right person is in prison. There are so many twists and turns, but we'll let the viewer decide what they think, George. Okay. You can see that at 9:00, 8:00 Outside right now, we have
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