This chest spawns as you complete raid event "The Order of Three" (see this quest entry for information).
Archon Epaulets
Baronth, Defender of Law
Book of Law
Cape of Control
Decree, Blade of Justice
Empowered Trophy of Order and Law
Ethic, Scepter of Law
Glowing Alaran Periapt
Greater Alaran Periapt
Hathor, Scythe of Punishment
Mask of the Carnifex
Median Alaran Periapt
Ostentatious Armwraps of Ryken
Ostentatious Footwraps of Ryken
Ostentatious Handwraps of Ryken
Ostentatious Headdress of Ryken
Ostentatious Legwraps of Ryken
Ostentatious Stole of Ryken
Ostentatious Wristwraps of Ryken
Pauldrons of Punishment
Rule
Shifting Sphere of Veiled Ascension
Trophy of Order and Law