Additional Sessions Judge Jasbir Singh Kundu junked the appeal of the student along with other two pleas in the case.
The court had earlier granted time till July 4 to the CBI to file a supplementary charge sheet in the murder case of a seven-year-old boy at a school here.
Advocate Sushil Tekriwal, lawyer for the seven-year-old victim, had argued that the JJB's order declaring the 16-year-old accused as an adult was "well-reasoned" and there was no fault and "nothing illegal" in it.
The counsel for the a 16-year-old accused had challenged the JJB order, saying it was "bad in law" and passed without giving him proper opportunity to present his case.
Earlier, the court had barred the media from using the name of the 16-year-old juvenile accused in the case and asked it to use fictitious names instead.
While the seven-year-old victim was named "Prince" by the court, the juvenile accused was named "Bholu" and the school was referred to as "Vidyalaya".
The CBI, in a charge sheet, had alleged that the teenager had murdered the student on September 8 last year in a bid to get the examinations postponed and a scheduled parent-teacher meeting cancelled.
The victim's body, with the throat slit, was found in the washroom of the school.
The probe agency gave a clean chit to school bus conductor Ashok Kumar, who was earlier arrested by the Gurgaon Police, saying there was no evidence to prove his involvement in the crime.
The CBI had taken up the case from the Gurgaon police on September 22, following a nationwide uproar over the gruesome killing.
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