A forensic expert in Ghaziabad special court on Monday could not answer some defence queries on samples lifted from the scene of the Aarushi-Hemraj double murder, a lawyer said.
Defence lawyer Manoj Shishodia said the Central Forensic Science Laboratory BK Mahapatra said he did not remember from which place at the murder spot he lifted which sample.
Mahapatra had visited the spot along with 12 other scientists on June 1, 2008.
Aarushi, 14, was found murdered at her parents' Noida residence on May 16, 2008. The body of Hemraj was found the next day on the terrace of the house.
The cross-examination of Mahapatra was held for the fifth day before the Central Bureau of Investigation (CBI) special judge S Lal.
The court adjourned the proceedings till Tuesday, Shishodia said.
The defence lawyer said Mahapatra said in the court that he did not remember whether a pillow found in Aarushi's room was of her own or of somebody else.
He said that Mahapatra's statements pointed that the CBI had failed to establish the crime scientifically.
Shishodia said that when the expert was asked whether he clicked photos of the articles collected for performing tests as per the rules laid down by the National Accreditation Board of Testing and Calibration Laboratories (NABL), the scientist answered in negative.
The scientist claimed that the CFSL followed its own manual, he said.
Teen Aarushi's father Rajesh Talwar and mother Nupur Talwar are the accused in the double murder.
Nupur Talwar was taken into custody on April 30 and she challenged in the apex court the May 31 Allahabad High Court order rejecting her bail plea. She is lodged in Dasna jail in Ghaziabad. Her husband is out on bail.