Civil Procedure II

Collateral Order Doctrine

An interlocutory order is appealable under the collateral order doctrine if it meets three conditions:

1. It conclusively determines the disputed question.
2. It resolves an important issue completely separate from the merits of the action.
3. It must be effectively unreviewable on appeal from a final judgment, as the right asserted would be essentially destroyed.

The collateral order doctrine is extremely rare.