Investigators searching for an ex-police officer's wife are focusing on the Global Positioning System in her husband's vehicle along with "biological material" and other physical evidence, according to a published report.
The Chicago Tribune reported in its Thursday editions that it obtained a warrant served on Drew Peterson in the investigation of his missing 23-year-old wife, Stacy.
The warrant called for the seizure of items containing plastic shavings, blood, bodily fluids, fingernail scrapings, palm or fingerprints, chemicals that may alter body decomposition and other "biological material that may be evidence of the offense of first-degree murder."
A separate warrant executed Nov. 1 and also obtained by the newspaper indicates authorities sought "all GPS records, cellular service records, logging records or any other electronic records in the possession of OnStar Inc." relating to a 2005 GMC Yukon Denali driven by Peterson.
The warrant did not say what investigators sought to learn from OnStar, General Motors' driver assistance subscription service. OnStar spokesman Jim Kobus said the service does not track subscribers' vehicles.
Tuesday's warrant omitted specific language about OnStar; in its place was a generic description that included "in-dash GPS navigation systems," according to the Tribune.
Joel Brodsky, Peterson's attorney, on Thursday told The Associated Press that the newspaper's description of the warrants "is accurate," but did not comment further.
Stacy Peterson was last seen Oct. 28 and reported missing by her family the next day. Drew Peterson, a longtime member of the Bolingbrook Police Department until he quit after his wife went missing, has denied any involvement in her disappearance. He has said he believes his wife left him for another man and is alive.
The most recent warrant also sought objects containing or having traces of blue plastic, lead weights, plastic shavings and scuff marks, circular impressions or carpet indentations and any other indication of a plastic or barrel-like object.
A nonprofit group helping to search for Stacy Peterson has said police asked them to look for a blue plastic barrel large enough to hide a body.
Authorities also are investigating the death of Peterson's ex-wife, Kathleen Savio, whose body was found in her bathtub in 2004. Her death initially was ruled an accidental drowning. But when Peterson disappeared, the Will County State's Attorney's office opened another investigation into the case and has said it appears her death was a homicide staged to look like an accident.