They have their internal ethics. We don't rat on guys, no cooperating with police, all that stuff. But the street code turned out to be a bunch of bullshit as guys started rolling over and singing as early as the 30's, with regular betrayals by the late 60's. By early 2000's even big bosses were ratting.
But anyway, I'll play along. Organizations that aren't criminally based, or advertised as such. It would be hard to beat the Clinton Foundation, or something like the Catholic Church. USADA isn't in the same universe as those orgs. Although in a sense it's unfair to compare, as this is a measure of impact on the world as opposed to "thorough corruption", regardless of impact. In that sense, USADA's thoroughly corrupt, like most large-scale charity orgs or churches.