The Third Circuit has concluded that a group cannot be designated as a Tier III terrorism group unless party leaders authorized the terrorist activity committed by its members.  "Still, the rule we announce today does not always require that the Government produce conclusive proof that the leader(s) of a group explicitly sign off on each individual terrorist act at issue. Instead, as the Board itself has opined in several cases, evidence of authorization may be direct or circumstantial, and authorization may be reasonably inferred from, among other things, the fact that most of an organization’s members commit terrorist activity or from a failure of a group’s leadership to condemn or curtail its members’ terrorist acts."

The full text of Uddin v.  Attorney General can be found here: