In March 1984 the Supreme Court ruled that the federal government owned the right to develop minerals on the continental shelf off Canada's coast. Peckford shifted his efforts to gaining joint management and most of the revenues from offshore oil resources and embarked on a cross-Canada tour to drum up support for the province's position. In the September 4, 1984, federal election Brian Mulroney's Progressive Conservative Party won a large majority government. Prior to the election Mulroney had agreed to a fair deal for the province with regards to offshore energy resources. On February 11, 1985, less than six months since Mulroney's election victory, both levels of government signed the Atlantic Accord. The Accord granted Newfoundland and Labrador significant decision-making powers and financial benefits. It made the federal and provincial governments equal partners in the management of offshore developments through the Canada-Newfoundland Offshore Petroleum Board. The Accord was widely hailed as a success for the Peckford administration and a turning point for the provincial economy.