Justice G.P. Mittal also held that charges of rape and unnatural sex cannot be sustained against prime accused Gopal Kanda.
"It is apparent that the ASJ (additional sessions judge) unjustly admitted into evidence the confessional statement made by the petitioner (Chadha) and illegally put the burden to prove the same on the co-accused (Kanda) and the petitioner which is not permissible," the court said.
Justice Mittal added: "The ASJ fell into gross error in framing the charge under Sections 376/377 (rape and unnatural sex) against the co-accused GGK (Kanda) which cannot be sustained. Since no charge against co-accused under these sections could have been framed, the petitioner could not have been guilty of abetting these offences."
The court's direction came on the plea of Chadha against framing of fresh charges of abetment of rape and suicide against her in the case.
The court, referring to Chadha's statement to police, held that except the disclosure statement, there was not even a shred of evidence to show that Kanda sexually exploited the victim and Chadha abetted in the commission of these offences.
"Apart from the supplementary disclosure statement of the petitioner AC (Chadha), there is nothing to indicate that co-accused GGK (Kanda) had illicit relations with 'X' (victim) or that she had multiple pregnancies...," the court said.
"All the more, there is not even a shred of evidence to indicate that co-accused GGK committed sexual intercourse with deceased 'X' or had carnal intercourse against the order of nature with her or that the same was against her (the deceased) will or without her consent or that the petitioner facilitated in any act of rape or unnatural offence alleged to have been committed by GGK," it added.
Justice Mittal, allowing the plea of Chadha, said: "...the petition is partly allowed to the extent that the framing of the charge for the offence punishable under Section 376/109 and Section 377/109 IPC is set aside."
The trial court had framed additional and fresh charges of rape and unnatural offence against Kanda and Chadha who was also booked for abetting the commission of these offences.
The high vourt held that some offences, including abetment of suicide, was made out against them, but there was no prima facie evidence indicating that they were also involved in the commission of rape and unnatural sex.
Justice Mittal also allowed another plea of Delhi Police for expunging the trial court's adverse remarks for not probing the sexual exploitation angle in the case.
Chadha and Kanda have been charged with rape, abetment of rape, abetment of suicide, criminal conspiracy, forgery under the Indian Penal Code and Information Technology Act for hacking computers and sending offensive or false messages.
The air hostess was found hanging from the ceiling fan of a room at her house in north Delhi Aug 5 last year.
She left behind two suicide notes blaming Kanda and Chadha, who are now in judicial custody, but have denied any involvement in the suicide.
In their charge sheet, police had said that Kanda was obsessed with the air hostess and he and Chadha had unleashed a series of wilful and malicious acts of mental torture, threat, blackmail and stress on her, which led her to take the extreme step.
Kanda was arrested Aug 18 last year after he surrendered at north Delhi's Ashok Vihar police, while Chadha was apprehended Aug 8. Police filed the charge sheet Oct 6.