The Council leader in 2267 was Tharn, who informed Captain James T. Kirk that the Federation's request to mine Halkan dilithium sources had been denied. In the mirror universe, the Halkan Council had the same legal powers and jurisdictions, but were willing to die to keep the Terran Empire from mining the dilithium sources from their planet. It was likewise led by Tharn. (TOS: "Mirror, Mirror" )