Here are some helpful tips to determine who should judge which spell (Light/Wisdom) during a boss fight.
Your primary judgment should be Judgment of Light based on 3.2 changes. The heath return is 2% of the attacker’s maximum health. Tanks have a highest pool of health, which makes this judgment the prime choice to use.
Your primary judgment should be Judgment of Wisdom. This is not due to retadin being a “replenisher” but more of maximizing your mana returns. Currently JoW mana return is limited to 15 PPM for spells and Physical since we utilize both we’ll see a few more proc with your mana return.
Holy can use either judgment of Wisdom or Light, if needed. If a holy paladin must judge during a fight then I would recommend Judgment of Light.
**Keep in mind judgments do not stack. The last person to judge will receive the credit of the effect. So it is important to communicate who is judging what to receive the maximum effect of the judgment.
Reference: Elitist Jerks