(NEW YORK) -- Surveillance footage shown in court of David Pietz, who is accused of killing wife Nicole Pietz, buying Drano and gloves on the night of her death, along with cellphone records from his wife's phone, have become the latest pieces of evidence in the puzzling case.
Nicole Pietz vanished from her home in 2006, and David Pietz was among those talking to reporters at the time, wondering where she was. Her body was later found strangled in a wooded area.
The shopping footage from a grocery store was the latest puzzle piece in a murder mystery seven years in the making. Since her daughter's disappearance, Nicole's mother, Gael Schneider, said she'd always suspected her son-in-law was the killer, and had hounded him incessantly until his arrest in March 2012.
In court, prosecutors didn't explain the Drano purchase but instead focused on a cellphone call they allege Nicole Pietz's 34-year-old husband made from his wife's phone, which was never found, after she disappeared.
A cellular telephone company engineer testified that global positioning from that call placed it very close to the gym where David Pietz worked.
Ashwani Goel, an AT&T wireless radio frequency engineer, agreed with the prosecution that there was a 90 to 95 percent probability that the phone was in the cellular sector of his gym when the call was placed. Prosecutors then went a step further, connecting the call to a surveillance tape from the gym showing Pietz absent from his work area at the time of the call.
The defense attorneys countered, pointing out that there were maintenance problems at the cell tower used to ID the call.
Goel confirmed the maintenance problems of the GPS locator. He said that technicians were at the gym's cellular sector on Jan. 26, and that they were there to troubleshoot performance problems.
David Pietz has pleaded not guilty.
"If they prove what they say they're going to prove, that still doesn't answer the question of how, why and when was she murdered," Pietz's defense attorney Mark Geragos said.
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