Any civilised society must try to punish such horrors. But in ending internal conflicts, peace, reconciliation and truth are as important as justice. There is often a trade-off. Rebels and dictators often refuse to give up unless they are promised amnesty. Moral imperative is thus tempered by political feasibility. And the politics is not getting much easier.
https://www.economist.com/the-americas/2019/06/29/are-amnesties-in-latin-america-always-a-bad-idea
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