Narco analysis on Aaftab Amin Poonawala, who is accused of killing his live-in partner Shraddha Walkar, will be conducted at Dr Baba Saheb Ambedkar Hospital in Rohini, New Delhi, most likely on Monday.
As Poonawala's five-day police custody ends on Tuesday, the Delhi Police is running against time to get the test conducted.
However, Poonawala can be subjected to narco analysis only after he is deemed fit for it in the pre-narco tests which will be conducted to ascertain his mental well being.
"We have not received any formal request from the police to conduct the test yet. But if the custody remand ends on Tuesday, we will comply with the court's order and take up the matter. However, no date has been fixed yet," a source in the hospital said.
"The FSL team will also be involved in the narco test. However, this will be done only after a medical officer gives his nod that the person is physically, mentally, emotionally and psychologically fit. Moreover, these tests take time.
"In this case, we are not aware if the accused has any medical condition or any psychological disorder. All these factors will have to be kept in mind before subjecting him to the tests. Only then can we move ahead with narco analysis," another source said.
In case Poonawala comes across as a 'disturbed' person during these initial tests, the narco analysis cannot be carried out, the source added.
Poonawala allegedly strangled Walkar, 27, on May 18 and sawed her body into 35 pieces which he kept in a 300-litre fridge for almost three weeks at his residence in South Delhi's Mehrauli before dumping them across the city over several days past midnight.
Narco analysis, also known as truth serum, involves intravenous administration of a drug (such as sodium pentothal, scopolamine and sodium amytal) that causes the person undergoing it to enter into various stages of anaesthesia.
In the hypnotic stage, the person becomes less inhibited and is more likely to divulge information, which would usually not be revealed in the conscious state.
The investigating agencies use this test after other evidences do not provide a clear picture of the case.
The Delhi Police had earlier said it sought Poonawala's narco analysis test as his responses during interrogation were 'deceptive' in nature.
The Supreme Court has ruled that narco analysis, brain mapping and polygraph tests cannot be conducted on any person without his or her consent.
Also, statements made during this test are not admissible as primary evidence in the court, except under certain circumstances when the bench thinks that the facts and nature of the case permit it.
Meanwhile, an undated CCTV footage is being circulated on social media in which a man, suspected to be Poonawala, is seen walking on a street with a backpack and a packet in his hand.
The footage seems to be of early hours of the day as there is darkness and does not show any other person.