The Delhi Police is seeking legal opinion on the ruling of the Juvenile Justice Board that the sixth accused in the gang-rape case was a "juvenile".
A decision on whether to go in for an appeal is expected to be taken soon.
A day after the Juvenile Justice Board gave its ruling that could enable the sixth accused to walk free by June 4 this year when he attains the age of 18 years, the Delhi Police has sought the advice of the legal experts in this case on whether an appeal could be filed in the Delhi High Court.
Highly-placed sources in the Delhi Police said a decision on whether to challenge the ruling is expected soon.
The sources said that there were other tests which could help in determining the age of the accused.
The accused, who was described as the most brutal of the six accused in the police charge-sheet, was declared 17 years and six months and 24 days-old (as of today) by the Juvenile Justice Board, which relied on his birth certificate and school documents produced before it.
They also said a supplementary charge-sheet in the case is expected to be filed soon in the court and that the post-mortem report of the victim has come from the Mount Elizabeth Hospital in Singapore where she breathed her last.
Soon after the ruling, the victim's family had yesterday demanded death penalty for the sixth accused in the incident. They had they would challenge the "unfortunate" decision of the Juvenile Justice Board.
"Sazaa kisi sey kam nahin honaa chahiye, chahey woh juvenile hai ya kuchh bhi hai (the punishment should not be less even if he is a juvenile," the 23-year-old paramedical student's father had said.
He said the punishment should be equal for all. "Sab ko barabar. Barabar maney phansi (same punishment for all, in other words death sentence)," he said.
"The family would consult legal experts and challenge the matter in the relevant court," the girl's brother said.