new delhi: the supreme court on friday reserved its verdict on the plea of union government to allow euro-ii diesel buses to ply in the capital along with cng buses even as mashelkar committee report on auto fuel policy came in for severe criticism. a bench comprising justice b n kirpal, justice v n khare and justice ashok bhan, after a marathon four-day hearing on the matter, reserved the verdict even as amicus curiae harish salve sought imposition of costs on the centre for making a deliberate attempt to misguide the court on the issue. salve said the court had categorically rejected all pleas relating to any modification in the earlier order making cng mandatory for the city bus fleet, but the government has again come with a request seeking permission to allow euro-ii diesel buses. he said there is a total lack of will on the part of both the centre and delhi government to implement the court orders, which have substantially reduced the pollution in the city attributable to vehicular emissions. salve said the mashelkar report on auto fuel policy by suggesting that fixing of pollution norms would be sufficient "runs in the teeth of the environment protection laws and should be declared to be so by the court." he said the court should consider implementing the principle of polluter pays while writing its verdict. on the extension of the january 31 deadline for conversion of the entire city bus fleet into cng mode, the court repeatedly asked the delhi government as to how they extended the deadline without consulting the court. however, during the hearing the court had made it clear that it was not going to recall any of its earlier orders making it mandatory for the 10,000-strong city bus fleet to convert into single fuel cng mode. in a spirited performance, additional solicitor general mukul rohatgi, appearing for the petroleum ministry, said cng was an evolving technology and no where in the world was there any conclusive proof to say that cng was better than 0.05 per cent sulphur content diesel. he said while cng had certain advantages in regard to emission of particulate matters, low sulphur diesel was prefarable for its low carbon monoxide emissions. questioning the ability of the high powered committee headed by retired bureaucrat bhure lal, rohatgi said, "is it right for a bureaucrat to decide that cng was the clean fuel when scientists across the world was debating over the issue? how can a bureaucrat decide what was the clean fuel?" countering this, amicus submitted central pollution control board reports which suggested that cng was a much cleaner fuel as compared to diesel. referring to the adulteration reports submitted by cse, rohatgi questioned the ability of the cse to conduct the tests saying it was manned by a professional anil agrawal who "unfortunately has passed away. and there are no professional there to conduct such tests." however, salve defended the tests saying all the results of the tests were recorded properly and added "just because the government was found on the wrong foot, all the test results have become a suspect".