This is the second time the defence has sought deferment of cross-examination of Central Forensic Science laboratory's senior scientist B P Mahaptra.
Although Mahaptra was cross-examined "partially" during the pre-lunch session, in the post-lunch session the defence sought deferment of further examination of the witness.
The plea was made on the grounds that none of the defence lawyers "is acquainted with forensic science" and hence "unable to cross-examine the forensic expert effectively", defense counsel Manoj Shishodia told PTI.
The defence lawyers also filed an application that the basis of Mahapatra's findings should be put on the case file in the court and they be allowed to inspect it.
Public Prosecutor R K Saini also filed an application before the CBI court stating that the defense be directed to complete the cross-examination of the witness.
The special CBI judge reserved the order for tomorrow on all the applications.
Aarushi, 14, was found murdered at her parents' Noida residence May 16, 2008 while the body of the family's domestic help Hemraj was found the next day on the terrace of the house. Aarushi's parents