Justice Mukta Gupta granted the parole to Singh for appearing in the final year examination of Master of Laws.
Singh had completed first branch of LLM in 2014 and thereafter took admission in the second branch.
The court said Singh's examinations are scheduled to commence from May 24 and he be released from jail from May 21 after the Delhi government did not oppose his plea.
Mattoo, 25, was raped and murdered in January 1996. Singh, a law student of Delhi University, was acquitted by the trial court in the case on December 3, 1999, but the Delhi High Court had on October 27, 2006 reversed the decision, holding him guilty of rape and murder and awarded him death penalty.
The son of a former IPS officer had challenged his conviction and death sentence awarded by the high court.
In October 2010, the Supreme Court had upheld Singh's conviction, but commuted the death sentence to life imprisonment.
During the day's hearing, Singh's counsel sought four weeks parole for appearing in LLM branch-II examination and for attending his daughter's birthday in June.
He said he had approached the jail authorities for the relief but they did not allow him due to the ongoing Lok Sabha elections.
The counsel said Singh's conduct in the jail has been good and he was also doing legal aid there.
Delhi government standing counsel (criminal) Rahul Mehra along with advocate Jamal Akhtar, filed a status report and nominal role of Singh and told the court that the convict has not misused the liberty granted to him earlier and was also studying in the jail.
They said Singh was in semi-open jail and the Delhi government's sentence review board has already recommended for his release.
After noting the submissions, the judge considered that he had not misused the liberty granted earlier and said the court deems it fit to grant parole to Singh for three weeks.
The court asked him to furnish a personal bond of Rs 25,000 and a surety of the like amount to the satisfaction of the superintendent of jail.
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