Legal Definitions - Cohen doctrine

The Cohen doctrine, also known as the collateral-order doctrine, is a narrow exception to the general rule that appeals can only be made after a trial court has issued a final judgment in an entire case. This doctrine allows for an immediate appeal of certain trial court orders, even if the main lawsuit is still ongoing.

For an order to be immediately appealable under the Cohen doctrine, it must meet three strict criteria:

• It must be a conclusive determination of the issue in question, meaning the trial court has made its final decision on that specific point.
• It must resolve an important issue completely separate from the merits of the main legal dispute. In other words, the issue being appealed is distinct from the core arguments of who wins or loses the case itself.
• It must be effectively unreviewable later, meaning that if the party appealing has to wait until the entire case is over to challenge the order, the harm caused by the order would be irreversible or the right being protected would be lost forever.

This doctrine is reserved for situations where delaying an appeal would defeat the very purpose of the right or protection at stake.

Here are some examples illustrating the Cohen doctrine:

• Example 1: Qualified Immunity for Government Officials

  Imagine a lawsuit against a police officer alleging excessive force. The officer argues they are entitled to "qualified immunity," which protects government officials from liability in certain situations. If the trial court denies the officer's claim of qualified immunity and orders the case to proceed to trial, the officer can immediately appeal that denial under the Cohen doctrine. This is because qualified immunity is designed to protect officials not just from liability, but also from the burden of *going through a trial* itself. If the officer had to wait until after a full trial to appeal the immunity denial, the protection from trial would have already been lost, making the appeal effectively useless.

• Example 2: Double Jeopardy Claims

  A defendant in a criminal case is acquitted of a crime. The prosecution then attempts to try the defendant again for the exact same offense. The defendant argues that this violates their Fifth Amendment right against "double jeopardy" (being tried twice for the same crime). If the trial court denies the defendant's motion to dismiss the second prosecution based on double jeopardy, the defendant can immediately appeal this decision. The right against double jeopardy protects a person from being *subjected to a second trial* for the same offense. If the defendant had to endure the entire second trial before appealing, the very right the Double Jeopardy Clause protects would be violated and could not be undone later.

• Example 3: Attorney-Client Privilege Disclosure

  In a civil lawsuit, a court orders a lawyer to disclose certain communications with their client, despite the lawyer arguing that these communications are protected by attorney-client privilege. The lawyer can immediately appeal this order under the Cohen doctrine. The attorney-client privilege is meant to keep certain communications confidential. If the lawyer were forced to disclose the information and then wait until the end of the entire case to appeal, the confidential information would already be public, and the privilege would be irrevocably breached, rendering a later appeal ineffective.