Designated Nationalist

A cross-community vote or cross-community support is a form of voting used in the Northern Ireland Assembly according to the provisions of the 1998 Belfast Agreement. It requires the support of both main communities in Northern Ireland, in other words majority of unionists and the majority of nationalist members of the Assembly. It is also used to a lesser extent at local government level.

Upon taking their seats members of the Northern Ireland Assembly are required to designate themselves as either "unionist", "nationalist" or "other". MLAs are free to designate themselves as they see fit, the only requirement being that no member may change his or her designation more than once during an Assembly session.

A vote will not automatically require cross-community support. A "Petition of Concern" must first be presented to the Speaker by at least 30 of the 108 members. In a cross-community vote the majority of unionists and the majority of nationalist votes are required to pass a motion put to the Assembly.

This was originally set out in the Northern Ireland Act 1998.

According to the standing orders of the Assembly, "after the signing of the Roll a Member may enter in the Roll a designation of identity, being Nationalist, Unionist or Other. A Member who does not register a designation of identity shall be deemed to be designated Other for the purposes of these Standing Orders."

Note: These figures include the assumed designation of the Speaker who, having a non-partisan role, does not officially declare a designation.

List of current and previous assembly parties by designation.

...
Wikipedia