 It was the second attempt to ratify the Maastricht Treaty, which could not come into effect unless ratified by all members of the European Union.Thus, the Edinburgh Agreement granted Denmark four exceptions from the Maastricht Treaty, leading to its eventual ratification.When the result of the referendum was announced, the outcome and frustrations about the referendum being held only a year after the Danes had rejected the previous treaty led to riots in the Nørrebro area of Copenhagen, 11 people were subsequently treated for gunshot wounds as a result of the shooting.