OTTAWA – The federal government has introduced tough new rules for supervised drug injection sites in a move some see as an effort to stamp out such facilities. The government says it’s a response to a Supreme Court of Canada ruling that ordered the Conservatives to keep a Vancouver clinic open against their will. But NDP health critic Libby Davies said the government is effectively blocking any chance of setting up a new clinic. The proposed legislation would require advocates of new clinics to meet two dozen specific criteria before they can apply. Among other things, they’d have to canvass community opinion and gain the support of provincial and municipal authorities.