Final answer:
The Collateral Order Doctrine allows certain non-final orders of a trial court to be immediately appealed. To be eligible for interlocutory appeals in federal court, the order being appealed must conclusively determine the disputed issue, resolve a separate important issue from the case's merits, and be effectively unreviewable on appeal from a final judgment.
Step-by-step explanation:
The Collateral Order Doctrine is a legal principle that allows certain non-final orders of a trial court to be immediately appealed, bypassing the usual requirement of waiting for a final judgment. To be eligible for interlocutory appeals in federal court, the Collateral Order Doctrine requires that the order being appealed must (1) conclusively determine the disputed issue, (2) resolve an important issue separate from the merits of the case, and (3) be effectively unreviewable on appeal from a final judgment. This doctrine is based on the idea that some orders are so important that immediate review is necessary to preserve important rights.