A bench of Chief Justice G Rohini and Justice Jayant Nath also said the Delhi government will have to admit that they do not have sufficient public transport to ferry people which was causing inconvenience to a large section of society.
"Aren't these six days enough for you? We have permitted the government to run this scheme for one week during which they must have collected data relating to pollution levels in the city," it said.
The court, however, fixed the matter for January 8 by when it has asked the government to get instructions on whether its pilot project can be reduced to a week instead of 15 days.
It also asked the government to provide data related to changes in the pollution level between January 1 and 7.
"In these six days you must have collected data related to pollution level, we think it's sufficient for you. You will have to think about inconvenience cause to public at large," the bench said, adding, "There is a practical difficulty."
It also said that the court does not interfere with the policies but government must think about it as people are knocking its door complaining of inconvenience being caused.
"You (government) have to think about it. Your status report is vague and does not reveal much," the bench said, adding, "There is no sufficient public transport. Is it really necessary to have it for 15 days?"
The court also wished to know from the government how many cabs are plying on diesel and CNG in the capital and what level of pollution were they emitting.
The court's direction came on a batch of petitions filed by various individuals including lawyers who have challenged the AAP government's December 28, 2015 notification bringing into force the scheme which allows private cars with odd-numbered plates to ply on odd-numbered dates and vice-versa.
While seeking quashing of the notification, a plea filed by Delhi high court Bar Association President Rajiv Khosla sought explanation from Delhi government on what jurisdiction it has to fix a fine of Rs 2,000 without amendment in the Motor Vehicles Act.
Opposing the move from various sections of the society, senior standing counsel Rahul Mehra, appearing for Delhi government, said "the scheme is only for 15 days and the state is equally pained by the inconvenience being caused to public."
The Delhi government, while replying to the court's query as to why women and two-wheelers were exempted from the scheme, said it was done as it is committed to provide security to women and restricting the two wheelers would have paralysed the transport system as there are no sufficient vehicles to cater such a huge demand.
"Since, motor cars shall be plied on alternate days according to their registration number being odd or even, it is perceived that their shall be rush in the public transport (metro and buses).
"Hence, the exemptions for women vehicles have been given to ensure that there is no compromise on women's safety," the Delhi government said.
It further said that a major portion of the population uses two-wheelers and pulling them out of the exemption would have led to congestion in public transport.
"The present number of vehicles are not sufficient to cater such a huge demand from the public," it said.
Mehra, the standing counsel for the AAP government, further submitted that there was prevalence of respiratory diseases among children and new borns and "we are levelled as the most polluted city in the world".
To this, the Chief Justice said "at present you are causing more inconvenience to public."
The bench also questioned the exemption granted to senior citizens and the car-pooling method saying the mechanism cannot be termed safe and could be misused in longer run.
It also asked the Delhi government to file an affidavit specifying the infrastructure for persons with disability in the public transport.
The bench also said that keeping lawyers out of the exemption list was also "practically unsound" and so the Delhi government needs to examine it.
The Delhi government counsel, however, said whatever it was doing was being done in the interest of people.
"We have to take into consideration the future of the next generation. Entire, world is considering climate change. We also have to move a step. Even Chief Justice of India and the judges of this court ... are supporting the scheme. Courts have been functioning well in the past few days," Mehra said.
The Delhi government counsel further submitted that had the people of Delhi not accepted the scheme, there would have been resentment.
"Can all this be equated with our health and health of our children? Do we all want our children to be on nebulizer? People of Delhi are responsible and only one or two per cent are opposing it. Right to Life has to be with clean health and we cannot skirt the issue," Mehra said.
He was responding to the pleas filed by the lawyers, who claimed that the scheme had been brought out and made applicable without even carrying out any feasiblity study and was hampering the legal fraternity in carrying out their professional responsibility.
One of the petitioners submitted that the notification has not assigned any reason for exempting categorised vehicles and hence was liable to be set aside.
"The notification is suffering from legislative incompetence and further the state government did not have the authority and jurisdiction to formulate a policy and further had no power to fix a fine of Rs 2000 without there being an amendment to the Motor Vehicle Act by the competent legislative forum," Khosla argued.
The bench, however, refused to pass any interim order on a bunch of 11 petitions filed by different individuals against the AAP government's plan on the odd-even scheme.
The vehicles exempted from the scheme include the President, Vice President, Prime Minister, Chief Justice of India, Union Ministers and Governors and Chief Ministers of states and Union Territories "except that of Delhi".
Besides, women drivers, CNG-certified vehicles, VIPs, two-wheelers, ambulances, defence vehicles and embassy vehicles have been exempted from the government's ambitious scheme.
Earlier, the high court had refused to pass any interim direction on the PILs, saying "Delhi government has proposed an idea, which is to be implemented from January 1, 2016, on trial basis for 15 days. Let them (Delhi government) try it."
The court's oral observation was made during hearing the PILs, filed by Shweta Kapoor and Sarvesh Singh, which sought directions for restraining implementation of policy.
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