Secret Jail Recording May Doom Kidnapping Suspect Man's alleged confession was 'off the record' to a reporter but not the FBI By Michael Harthorne, Newser Staff Posted Sep 3, 2015 6:38 PM CDT 13 comments Comments Matthew Muller is shown here. (AP Photo/Dublin PD) (Newser) – "Off the record" doesn't mean the same thing in jail. It's a lesson Matthew Muller may learn the hard way. The Harvard graduate and respected immigration lawyer—suspected in at least five kidnappings in California over the past six years—may be undone because a prison interview he gave to a local TV reporter was secretly recorded, Wired reports in a thorough look at the bizarre case. Muller was arrested in June after allegedly kidnapping a 29-year-old woman and releasing her 400 miles from home, then leaving his cellphone at the scene of a second, failed kidnapping, Wired reports. Police now believe he was responsible for two similar crimes in 2009 and another in 2012. Reporter Juliette Goodrich of KPIX-TV visited Muller in jail in July and was granted an interview, though the two had to speak over the phone through a glass partition. While some of that interview was "off the record" and never reported, the entire thing was recorded by the jail and handed over to the FBI, Wired reports. According to a recently released FBI affidavit, Muller confessed his guilt during that interview. And that's important because the rest of the evidence against him could be thrown out if it's found police illegally searched his cellphone. "There are signs, and you're notified that visits are recorded," one of the victim's lawyers tells Wired. "Speak at your own peril." For more on the strange kidnappings—multiple drones, victims drugged with NyQuil, mysterious disappearances—read the whole story here.