The inmate who claims he overheard double murder suspect Scott Peterson (search) talking about kidnapping his wife Laci convinced the ex-cop who gave him a polygraph test that he is telling the truth, the officer told Fox News in an exclusive interview.
"Mr. Carroll was able to convince me that he truly believes what he's saying has some validity to it," King said.
King, who has dealt with numerous inmate witnesses in the past, said they typically ask to cut some sort of deal for a plea bargain. But Carroll was different, he said.
"He was just the opposite," King told Fox.
Peterson, 30, is accused of killing his wife Laci Peterson, 27, and unborn son, Conner.
Carroll, a self-described petty property criminal, told investigators he first met Peterson last November at the City Lights strip club in Fresno, Calif.
After a conversation in which Carroll revealed he had been in prison, Peterson asked for help in finding someone to steal his wife’s car as part of an insurance fraud scheme, according to a report in the Modesto Bee.
Carroll, 34, told King he then introduced Peterson to two members of a neo-Nazi prison gang known as the Nazi Low Riders (search). He was paid $300 to set up the meeting, according to the Bee.
Carroll claims he and the two men -- Tony, aka “Dirty,” and Anthony, aka “Skeeter" -- met with Peterson in a northeast Fresno restaurant on or about Nov. 29. The four went on to a nearby motel.
At the motel, Carroll said he overheard Peterson talking about kidnapping his wife Laci and getting ransom money from her parents, King told Fox.
Carroll said he told the men he didn't want to hear or know anything about such a scheme and abruptly left the room, according to King. Carroll's attorney Frank Muna told Fox his client was away from the meeting for about 45 minutes.
But Peterson's sister-in-law, Janey Peterson, told Fox News she was with Scott and Laci in San Diego on Nov. 29, two days after a baby shower had been held there for Laci.
Calling Carroll’s claims “all lies,” she said it would have been impossible for Peterson to have left San Diego midday, driven more than seven hours to Modesto, dropped off his wife and presents at their home and driven another hour-plus to Fresno for the alleged meeting.
Janey Peterson said she was trying to confirm the exact time Scott and Laci left San Diego that day.
Carroll's lawyer Muna told Fox News that his client disclosed his story only after recognizing Peterson on television after his April arrest for the murders of Laci and Conner.
Muna said he notified law enforcement after his client passed the polygraph administered by King.
Polygraph examinations are not admissible in court. But a memo summarizing the test obtained by the Bee shows Carroll correctly identified the model of Peterson’s Ford F-150 pickup.
In addition, a van like the one "Dirty" and "Skeeter" had was described by a witness as having been across the street from the Peterson home the day of Laci's Dec. 24 disappearance.
Police have since downplayed reports of a so-called suspicious van.
Investigators involved in the case would not comment on Carroll’s claims to the Bee due to a court-imposed gag order.
In other case news, sources close to Peterson told Fox News there had been ongoing discussions among family members about potentially decreasing the role of lead attorney Mark Geragos (search).
Several members of Peterson's family are said to be frustrated with his representation and believe they are "paying a lot of money and not getting a lot in return," one source said.
But the sources said family members were divided on the matter. Peterson's mother Jackie Peterson told Fox Tuesday night that she was happy with Geragos.
Tossing Geragos or scaling back his involvement at this stage could cause serious problems for Peterson's defense, since the Oct. 20 preliminary hearing is less than a month away.
Fox News' Geraldo Rivera, Rita Cosby and Catherine Donaldson-Evans contributed to this report.