DUBLIN — The British government announced Thursday it will appoint a judge to investigate its long-secret policy of supplying letters to Irish Republican Army fugitives promising them protection from arrest. The issue is dividing Northern Ireland’s unity government. Why? The AP explains. Making peace with the IRA The main branch of the Irish Republican Army, the Provisionals, killed nearly 1,800 people during a 27-year campaign to force Northern Ireland out of the United Kingdom.