Preventing subsequent litigation: res judicata and abuse of the court process

by Practical Law Dispute Resolution

A practice note that provides guidance on how the courts in England and Wales will consider whether litigation should be prevented or struck out based on the principles of res judicata or as an abuse of process. This practice note explores the circumstances where a claim raises issues that have been, or could have been, decided in previous proceedings, or where it constitutes an attack on a prior decision. This practice note examines the two main branches of res judicata: issue estoppel and cause of action estoppel. It also details abuse of process under CPR 3.4(2)(b) and the court's inherent jurisdiction, with a focus on the key principles from Henderson v Henderson and the concept of collateral attack. Guidance is provided on the application of these doctrines in various contexts, including foreign judgments, specialist litigation such as tax and patents, and disciplinary proceedings. This practice note also covers related topics such as the doctrine of merger and vexatious litigants, and the court's approach to its duty to prevent duplicative litigation, referencing principles in Johnson v Gore Wood. This practice note should be read alongside Practice notes, Strike out: an overview and The procedure for striking out. There is also some guidance on vexatious litigants and other court rules which may assist preventing successive litigation. Note: This practice note deals with abuse of process in the context of successive or repeated litigation. Abuse of process in other contexts is considered in Practice note, Strike out: an overview: Abuse of process (CPR 3.4(2)(b)).