The inquiry against the juvenile accused -- in the December 16 gangrape and murder of a 23-year-old girl in Delhi -- concluded on Friday before the Juvenile Justice Board which reserved its order for July 11.
The Juvenile Justice Board, presided by Principal Magistrate Geetanjali Goel, concluded its inquiry that began in March against the juvenile.
The police have claimed the juvenile was the "most brutal" of all the six accused.
After hearing the final arguments in the matter, the JJB reserved its order for July 11, saying the prosecution and defence could give any clarification they want to on that day, police sources said.
The JJB also concluded its inquiry in the case against the juvenile pertaining to robbing Ramadhar, a carpenter who had boarded the bus on the night of December 12, 2012.
He was thrown out of the bus before the girl and her friend were assaulted.
The girl had died in a Singapore hospital on December 29.
The juvenile is a native of Uttar Pradesh who had moved to Delhi as an 11-year-old and taken up menial jobs.
While the juvenile faces an inquiry before the JJB, the four adult accused are being tried before a fast track court.
Key accused Ram Singh was found hanging in Tihar Jail in March and the proceedings against him stand abated.
During the inquiry, the JJB recorded the statements of six prosecution witnesses, including the victim's male friend and the carpenter.
The counsel for the juvenile had submitted that there was no medical evidence against him to connect him with the charges and no finger prints could be detected in the bus to show his complicity, the sources said.