They were suppressing technology, per a treaty with the Pa'anuri. It was appeasement, writ large, for hundreds of thousands of years.
Their clone-and-interrogate operation probably killed the equivalent of the entire population of the galaxy a few thousand times over.
But you and I are able to stand here and argue the morality of it, so on some level it must have worked, right?
Yeah... umm... I'm ready to talk about something else now.