Transcript for David Pietz Midnight Shopping Trip Video Played in Court
seattle man, on trial for murdering his wife, more than seven years after his death. The prosecution laying out key evidence, including a suspicious video. And abc's neal karlinsky has the latest. Reporter: On the night that police say nicole pietz was murdered in 2006, this was her husband, david, three minutes before midnight on a seemingly odd shopping trip. Do you recall any of the items? Drano and gloves. Reporter: It is the latest puzz piece in a murder mistake seven years in the making. Seven long years of nicole's mother hounding david pietz. Always believing he killed nicole, strangling her and leaving her body in the woods, to escape their marriage for a slew of other relationships. In court, prosecutors didn't explain the drano purchase. And then, focused on a suspicious cell phone call made after the disappearance, made with nicole's phone that was never found. A cell phone company engineer said that gps placed it close to the gym where david pietz worked. There's a 90% probability that the phone was in this reddish/orangish sector when it was being placed? That is correct. Reporter: Prosecutors went a step further. Connecting the call to this surveillance tape from the gym. Showing pietz gone from his work area at the time of the call. Even this was countered with serious questions. Defense attorneys pointing out maintenance issues with the cell tower used to i.D. The call. The reason the technicians WENT THERE ON JANUARY 30th, 2006, and it's indicated in the records, they were here to troubleshoot performance issues with sector c. That is correct. Reporter: David pietz has pleaded not guilty. And so far, it appears, prosecutors have no smoking gun. If they prove what they say they're going to prove, that still does not answer the question, how? Why? And when was she murdered? Reporter: For "good morning america," neal karlinsky, abc news, seattle. Let's go over this evidence with dan abrams. Starting with the surveillance at the supermarket, what does that prove? It could suggest he wanted to do deep cleaning at his house. And it could suggest that he wanted to do deep cleaning at his house. It's how you look at the exact same pieces of evidence. It's not helpful to him that he's going in at midnight, about a day and a half before this happens and purchasing the sort of items one would purchase or night purchase to clean up a crime scene. On the other hand, the defense is saying, that's all great. But you haven't been able to link that back to this particular crime. So, interesting somewhat. I would describe it as an important piece of evidence. But not make or break piece. The cell phone. That's potentially make or break. That's really important in connection with this case. They're showing that she couldn't make the phone call. They're trying to suggest that he had her phone and was using it to make a call to make it seem like she was still alive, at that time. One of the reasons this case wasn't charged earlier was because they didn't have some of the cell phone records. This becomes a crucial piece of evidence in connection with this case. Okay. Dan abrams, thanks very much.
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