The CPI today demanded an effective probe into the 2G spectrum scam, including by a joint parliamentary committee. Speaking to reporters, CPI leader Gurudas Dasgupta said the resignationby Telecom Minister A Raja does not absolve him of personal responsibility in the 2G spectrum. He also demanded cancellation of all illegal orders and compensation of losses suffered by the exchequer by the people who are benefited by the dubious deals. He said the government should end the impasse to see that Parliament runs smoothly.