New York ( CNN ) -- A lawyer for a man accused of killing 6-year-old Etan Patz in 1979 says his client falsely confessed to authorities in May and will plead not guilty when he is arraigned next month . The attorney 's statement Thursday morning came after Pedro Hernandez made a brief appearance in Manhattan criminal court . `` The statements by my client ( to police last spring ) are not reliable , '' defense attorney Harvey Fishbein said . `` They are what we term false confessions . '' A grand jury on Wednesday indicted New Jersey resident Hernandez on charges of second-degree murder first-degree kidnapping . At Thursday 's hearing , a judge transferred the case to New York State Supreme Court -- the state 's main trial court system -- in Manhattan and set an arraignment for December 12 . Missing child case 'awakened America ' Police said Hernandez in May confessed to killing Patz , who disappeared on his way to a New York school bus stop more than 33 years ago . Hernandez -- who was a stock clerk in Lower Manhattan in May 1979 -- admitted that he choked the boy after luring him into the basement of a Manhattan grocery store , police said . Hernandez allegedly told authorities that he threw away the boy 's body in a garbage bag . The remains have not been found . Etan disappeared on May 25 , roughly a month before Hernandez left New York to resume living at his mother 's south Jersey home , according to family members and police . Fishbein has claimed Hernandez has been repeatedly diagnosed with schizophrenia , and that he has `` an IQ in the borderline-to-mild mental retardation range . '' Patz investigation a 33-year-long roller coast ride . On Wednesday , district attorney spokeswoman Erin Duggan said the indictment was `` the outcome of a lengthy and deliberative process , involving months of factual investigation and legal analysis . '' `` We believe the evidence that Mr. Hernandez killed Etan Patz to be credible and persuasive , and that his statements are not the product of any mental illness , '' she said Wednesday . Besides arguing that the confession was false , Fishbein said he would argue that the prosecution has insufficient evidence , and that the statements Hernandez made to police are inadmissible . Patz 's plight catapulted concern for missing children to the national forefront after authorities put his image on thousands of milk cartons , a technique that would become more common in the next few years . Opinion : Missing children , perception vs. reality . CNN 's Ross Levitt and Jason Hanna contributed to this report .
Suspect in 1979 disappearance of New Jersey boy will plea not guilty , his attorney says . A grand jury indicted Pedro Hernandez in the case this morning . Hernandez 's statements to police are not reliable , his attorney says . Hernandez , charged with murder , confessed to killing the year - old , police say .