Throughout its existence, republican political leaders and most Roman Catholic clerics discouraged Catholics from joining the RUC. Seamus Mallon, Social Democratic and Labour Party Member of Parliament (MP) and critic of the force, who later served as Deputy First Minister of Northern Ireland, stated that the RUC was ""97% Protestant and 100% unionist"". The RUC did attract some Roman Catholics, mostly former members of the RIC, who came north from the Irish Free State after the bitterness of the fighting during the Anglo-Irish War largely precluded them from remaining in territory now controlled by their enemies. The percentage of Catholics in the RUC dropped as these men retired over time.