A Canadian lawmaker resigned from the governing Liberal Party on Monday because of his opposition to its efforts to legalize gay marriage, further weakening Prime Minister Paul Martin's minority government. Parliament member Pat O'Brien declared himself an independent, taking a seat away from the Liberals. The move comes shortly after Martin's scandal-battered minority government won a no-confidence motion in parliament by just one vote. O'Brien's defection does not dramatically change the balance of power for the Liberals, since an opposition Conservative Party member crossed over to the Liberals and another Liberal was recently elected in a by-election. But his departure gives impetus to the growing push by other Liberals to join Conservatives in blocking the gay marriage bill.