At the most extreme interpretation, slavery is legal under islamic law - see Sultanhussein Tabandeh, "A Muslim Commentary on the Universal Declaration of Human Rights". And the Cairo Declaration says that there is no crime except that proscribed by sharia. Countries like Saudi Arabia and Yemen had slaves well into the 20th century (a 1951 UN report estimated that 5% of the population of those countries were slaves), and they only "outlawed" slavery under duress from the west. There is still slave-taking and trading in Mauritania and Sudan.
There are now plenty of serious works on the 1300 years of the islamic slave trade, e.g.
It beggars belief that Amnesty can simply ignore it when the islamic world rejects universal human rights. But as long as Amnesty ignores it, the OIC's Cairo Declaration can fly under the radar, and be ignored by mainstream media and governments.
My understanding of the Cairo Declaration might be wrong. But until it starts to be discussed by organisations like Amnesty, it is not going to be subjected to extensive critical examination.
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