Leaving will mean less communication with other security services  Leaving the EU may damage relationships with key security partners such as France and Germany. Both countries would have much less reason to cooperate on security issued when not in the same organisation. There would certainly still be some cooperation but the former heads of Mi5 and Mi6, Lord Evans and Sir John Sawers have stated that the UK would lose out through not being able “to take part in the decisions that frame the sharing of data, which is a crucial part of counter-terrorism and counter-cyber work”. Sawers points out that data sharing in the EU allowed France to transfer DNA and fingerprints of one of the Brussels bombers within months – previous to EU data sharing it would have taken months slowing down critical investigations. [1]  [1] ‘Row as ex-intelligence chiefs say EU membership protects UK security’, BBC News, 8 May 2016,