Sinn Fein members voted on Sunday to begin cooperating with the Northern Ireland police, formally abandoning their decades-old hostility to legal law and order in the British territory.The result—confirmed by a sea of raised hands but no formally recorded vote—represented a stunning triumph for Sinn Fein chief Gerry Adams, the former Irish Republican Army commander who has spent 24 years edging his IRA-linked party away from terror and towards compromise. It strongly improved the chances of reviving a Catholic-Protestant administration, the long-elusive goal of the 1998 Good Friday peace pact, by Britain's deadline of March 26.Earlier, Adams, addressing over 2,000 activists at debate at the Royal Dublin Society conference hall, had said, “Some of you will no doubt disagree. And that is perfectly acceptable.” But he said he and unnamed “very senior republicans” had decided two months ago that political progress “requires a policing deal . so the time is now right.”