NEW YORK, Sept. 29 (UPI) -- Former Illinois police officer Drew Peterson says he can't explain why a polygraph suggested he deceptively answered questions about his missing wife.
Peterson, a former Bolingbrook, Ill., police sergeant, is a suspect in the disappearance of his fourth wife, Stacy, in October 2007, the Chicago Tribune and the Chicago Sun-Times have reported.
Peterson, who has not been charged with a crime and has denied any wrongdoing, said Monday on the CBS "Early Show" that he passed a polygraph regarding the death of his third wife, Kathleen Savio, who was found dead in the bathtub in the couple's home in 2004.
Savio's death was ruled accidental until this year, when her body was exhumed and her death determined to be homicide, police have said.
On a polygraph exam regarding Stacy Peterson, an answer regarding her whereabouts was determined to be deceptive, said Drew Peterson, noting he took the polygraphs for a book he is writing.
Peterson told CBS he was asked, "'Do you know the whereabouts of your wife Stacy?' I answered no, and the results showed that was deceptive," Peterson said, adding that he could not explain the polygraph's conclusion.