Due in large part to Lemass' organisational skill, most of Sinn Féin's branches defected to Fianna Fáil. This enabled the new party to make a strong showing at the June 1927 election, taking 44 seats while reducing its parent party to only five. More importantly, this was only three seats behind the governing party, Cumann na nGaedheal. Pending the removal of the Oath of Allegiance, the party announced that it would not take up its Dáil seats. A court case was begun in the name of Lemass and others. However, the assassination by the IRA of Kevin O'Higgins, the Vice-President of the Executive Council (deputy prime minister), led to the passing of a new Act requiring all prospective Dáil candidates to take an oath that, if elected, they would swear the Oath of Allegiance; a refusal to do so would prohibit anyone from candidacy in a general or by-election.