Malta exiles

After World War I, the effort to prosecute Ottoman war criminals was taken up by the Paris Peace Conference (1919) and ultimately included in the Treaty of Sèvres (1920) with the Ottoman Empire. The Ottoman government organized a series of courts martial in 1919–1920 to prosecute war criminals, but these failed on account of political pressure. The main effort by the Allied administration that occupied Constantinople fell short of establishing an international tribunal in Malta to try the so-called Malta exiles, Ottoman war criminals held as POWs by the British forces in Malta. In the end, no tribunals were held in Malta.

According to European Court of Human Rights judge Giovanni Bonello the suspension of prosecutions, the repatriation and release of Turkish detainees was amongst others a result of the lack of an appropriate legal framework with supranational jurisdiction, because following World War I no international norms for regulating war crimes existed. The release of the Turkish detainees was accomplished in exchange for 22 British prisoners held by Mustafa Kemal Atatürk.

Since there were no international laws in place under which they could be tried, the men who orchestrated the genocide escaped prosecution and traveled relatively freely throughout Germany, Italy, and Central Asia. This led to the formation of Operation Nemesis, a covert operation conducted by Armenians during which Ottoman political and military figures who fled prosecution were assassinated for their role in the Armenian Genocide.

Following the reportage by Henry Morgenthau, Sr., US Ambassador to the Ottoman Empire, of the Armenian resistance during the Armenian Genocide at the city of Van, the Triple Entente formally warned the Ottoman Empire on 24 May 1915 that:

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