Metropolitan Magistrate Deepak Wason in his order passed recently pulled up police for conducting the investigation in a casual manner and said that various material aspects of the October 2008 incident were overlooked.
The court has now ordered a senior police officer to conduct investigation in the matter and submit a report within six months.
According to a police, Ashish Pal's body, with a gun shot injury on his forehead, was found in his bedroom in Narela Oct 26, 2008. There was a pistol in the right hand of the victim. A post-mortem report said that he died on the night of Oct 25.
Police July 20, 2010 filed a final report in the case, claiming that Pal committed suicide.
The court observed that police failed to collect any document on record to suggest the reason for which Pal, a married man, committed suicide.
"A perusal of record shows that the investigating officer of the case did not take the finger prints from the weapon which has been used in the present case," said the court in an order made available Saturday.
The victim's brother Mahavir Singh Khatri earlier alleged that Ashish was driven to suicide. He moved the Delhi High Court which added abetment to suicide charges to the first information report registered in the case.
The trial court said that the photographs of the body showed that there was no blood on the wound, no part of the body was stained with blood and there was no blood found on the victim's hand holding the pistol.
The court observed that the bullet, which allegedly killed Pal, was found after 10 days of the incident by forensic experts team from the mattress on which his body was found.
The trial judge was surprised that there was no hole in the bed sheet on which the body was lying despite the fact that the bullet was recovered from the mattress under it.
"The bullet might have pierced the bed sheet before entering the mattress. Further, photographs also show that the deceased was lying on the bed sheet and the bed sheet was fully covered on the mattress," said the court.
The court said that the post-mortem report also raised doubts on Pal's suicide. The statement of Pal's wife said that he consumed alcohol but the victim's medical report denied it.
Police have not investigated whether Pal had good or strained relations with his relatives, the judge said.
The investigation would now be conducted by a senior officer of the special staff of the outer police district, ruled the court.