Danish European Union opt-outs referendum

Denmark holds opt-outs from European Union policies in relation to security and defence, citizenship, police and justice, and the adoption of the euro. They were secured under the Edinburgh Agreement in 1992 after a referendum for the ratification of the Maastricht Treaty was rejected by Danish voters, as a package of measure to assuage concerns raised during that referendum.

The Danish governments has held two referendums on modifying its opt-outs. The first in 2000 rejected the adoption of the euro by 53.2% to 46.8% on a turnout of 87.6%. The second in 2015 rejected converting Denmark's current full opt-out on home and justice matters into a case-by-case opt-out similar to that currently held by Ireland and the United Kingdom by 53.1% to 46.9%.

Denmark obtained four opt-outs from the Maastricht Treaty following the treaty's initial rejection in a 1992 referendum. The opt-outs are outlined in the Edinburgh Agreement and concern the Economic and monetary union (EMU), the Common Security and Defence Policy (CSDP), Justice and Home Affairs (then JHA, now PJCC) and the citizenship of the European Union. With these opt-outs the Danish people accepted the treaty in a second referendum held in 1993.

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