Former Unity MP for Mid-Ulster Bernadette McAliskey served on the executive of the IRSP. She resigned following the failure of a motion to be passed which would have brought the INLA under the control of the IRSP "Ard Comhairle" (executive committee). This led to the resignation of half the "Ard Comhairle", which weakened the party. Tony Gregory, a future Dublin TD, was also a member for a short time. Its poor showing in the 1977 Irish general election, and the assassination of Seamus Costello, weakened the organisation.