Joseph Edward Duncan III

Memorial for Anthony Martinez

Earlier, when Duncan had agreed to speak with FBI agents during the initial investigation, he had mentioned ten-year-old Anthony Martinez's name. Aware of the Martinez case and very interested, the FBI agents contacted Riverside County Sheriff Bob Doyle in California.

"It was a situation where they were asking him about his involvement in any other similar case," Doyle told a reporter with the National Enquirer. "He said, 'Yeah, this boy Martinez in southern California, Riverside County.' It was not a full, blown-out confession, though. The FBI asked us if we knew anything about a Martinez case. I said, 'We sure do — we've been trying to solve the murder for years, and we've gone through 15,000 leads.' So when we were able to match a partial thumb print on duct tape found near Anthony's body with that of Duncan, we knew we had our man."

Doyle initially had sent investigators to the Kootenai County Jail in Coeur d'Alene, Idaho to interview Duncan, but he refused to speak with them.

"We haven't charged him yet, but we intend to carry out further investigations," Doyle said after the 2006 attempt to interview Duncan. "And we are certainly looking to interview him again."

Anthony Martinez's mother, upon learning of the circumstances of Duncan's parole after serving only 14 years of a 20-year sentence that had allowed him to commit such savagery upon the Groene and McKenzie families and to murder her own young son, was outraged.

"How do you get out for good behavior?" she asked. "Someone like that can't be rehabilitated. I don't care what psychologists say."

After linking Duncan to Anthony Martinez's death, the FBI began looking into the possibility that there might be other murders that could be linked to Duncan that had remained unsolved throughout the years. For all they knew, there could be many.

According to retired lieutenant Mitch White, the lead investigator in the Martinez case who spoke with KPSP News, the search for Anthony had been a race against time in hopes of finding the boy alive after learning of his kidnapping at knifepoint in the alley behind his house. He said that there had often been more than 60 investigators each day working on the case in the field "following up on leads—at least until his body was found down in Indio."

"When his body was found it was like letting the air out of a balloon," White said. "I mean, everyone was deflated. A lot of people were angry that it hadn't worked out the way they hoped it would... Once [Anthony] was found, [investigators] moved down to Indio and continued for a few months after that with a huge investigation."

Anthony had been missing for 15 days when his body was found in a remote area south of Joshua Tree National Monument in Indio, bound with duct tape, raped, tortured and then beaten to death.