Useful to allow you to heal without interruption or to flee. This stun is one of the most flexible in the game, as it will not break due to damage or other spells being cast on the target, nor does it cause any amount of threat when used.
It cannot be used on a target that already has a Hammer of Justice stun active.
Most bosses and some high-level mobs are immune to Hammer of Justice.
Patch 3.2.0 (04-Aug-2009): Tooltip now specifies that the Interrupt effect only occurs on non-player targets.
Hotfix (2009-06-08): "When immune to the stun of following abilities, Maim, Bash, and Hammer of Justice will no longer cause player spells to be interrupted but they will still interrupt NPCs. Also, when these abilities do stun a player target, they will not perform an interrupt effect and lock out the affected magic school. As an example, if a Mage is channeling Arcane Missiles and is hit by Hammer of Justice, Blink will now be available as the Arcane school will not be locked out as it was before."
Patch 3.1.0 (14-Apr-2009): This ability will now still interrupt casting even if the victim is immune to the stun due to diminishing returns.
Patch 3.0.3 (04-Nov-2008): The interrupt from this ability will also be redirected when the stun is redirected. In addition, the interrupt will now work on targets immune to stun.
/Patch 3.0.2 (14-Oct-2008): Hammer of Justice now costs 3% of base mana.