 During his service in the Palestine Police, Cairns was accused of using torture against members of Irgun, including Irgun leaders Benjamin Zerony and Mordechai Pacho.This alleged torture of Zerony between 5–8 August 1939 resulted in a Palestine-wide leaflet being distributed by the Irgun announcing he was to be assassinated.Previous attempts to assassinate Cairns had been made earlier by shooting from the pillion of a motor cycle when he was walking with his German fiancé Marianna Laur in a local market.