On 4th December 2015, after a parliamentary debate on 2d December, the German Parliament decided, with 445 positive votes (146 negative votes and seven abstentions), to honour the German’s Government’s formal request (BT Drucksache 18/6866 of 1st Dec. 2015 ) to send up to 1200 troops to combat ISIS. A formal parliamentary decision to deploy military abroad is required by the German Constitution (Basic Law) and a German 2005 law (Parlamentsbeteiligungsgesetz) which codifies prior constitutional case law.
The international legal basis for the deployment decision, as officially claimed by the Government, is “Art. 51 of the UN Charter in conjunction with Art. 42(7) TEU as well as resolutions 2170 (2014), 2199 (2015), 2249 (2015) of the Security Council.” In its request to Parliament, the Government explained that action against IS (by the US, Australia, the UK, and France) “in exercise of collectives self-defence under Art. 51 of the UN Charter is covered by resolution 2249 (2015).” (BT Drs. 18/1866, p. 3). The EU-assistance clause as invoked by France on 13th November, to which all EU member States responded on 17th November with the promise for assistance, has been analysed here by Carolyn Moser. The substance of the IS resolution 2249 has been analysed on EJIL talk! by Marc Weller, by Dapo Akande and Marko Milanovic.