The agreement shall enter into force for those countries that approved it after ratification of 13 states (which must include France, Germany and the United Kingdom) and an adaptation of the Brussels I regulation.

The Danish Ministry of Justice issued its opinion in May 2013 that a referendum or five-sixths majority in the Folketing was necessary for the government to ratify the agreement due to constitutional requirements on the transfer of sovereignty.

[2][3] The Danish People's Party (DF) and the Red–Green Alliance, collectively controlling around one-fifth of the Folketing seats, stated their opinion that a referendum should be held.

[4] Despite being implored to negotiate with the DF by the leader of the opposition Lars Løkke Rasmussen, the government opted to hold a referendum,[1] announcing in December 2013 that one would go ahead on 25 May 2014.

[5] The legal basis for the referendum was sections 20 and 42 of the Constitution of Denmark according to which a majority consisting of at least 30% of the electorate could reject the decision of the Folketing due to it involving transfer of sovereignty.