Singh, on whose petition the "historic" order was delivered by the apex court, said, "It came at a time when there is a universal demand for amendments in the Code of Criminal Procedure (CrPC) and Indian Penal Code (IPC)."
He said poor prisoners were languishing in jails due to the prevalence of archaic and colonial law which have no relevance today on individual freedom and liberty.
"We have been following old British norms and legal standards which have no relevance today after 200 years of its formulations.
"The latest order delivered on September 5 is not only historic but this has also responded to the necessity of the present time to ensure protection of civil liberty and application of principle of natural justice," Singh, who is also the chief of Jammu and Kashmir National Panthers Party, said in a statement.
The senior advocate, who is also espousing the cause of several prisoners of foreign nationalities, including Pakistanis, said,"This order has brought great innovation and unique revolution as it will be applicable to all prisoners irrespective of their nationality."
Further, he said the order on the petition, which he has been pursuing since 2005, would also be applicable to those convicted persons, who have spent half their quantum of punishment in the jail during pendency of their appeals in the higher courts.
Singh said the order was unique as it has made a departure from traditional criminal jurisprudence by making "duty bound" the chief judicial officer/sessions judge of the country that they have to visit the prisons under their jurisdiction and decide the status of all undertrials on the spot on the basis of the record of each inmates.