Consolidation of lawsuits may be ordered by a court when two or more lawsuits involving the same or similar parties (plaintiff and defendant), legal issues, and factual issues are pending in the same court or in different courts in the same jurisdiction (state court system or federal court system). If the lawsuits are pending in different courts one case may be transferred to the other court, and the cases consolidated there.

Laws and rules regarding the consolidation—or transfer and consolidation—of lawsuits vary from state to state and in the federal court system.

In Connecticut, the consolidation of lawsuits is governed by state statutes and rules of civil procedure. According to the Connecticut Practice Book, which outlines the rules for civil proceedings, a court may order consolidation of lawsuits when there are common questions of law or fact to promote judicial efficiency and avoid inconsistent judgments. This can occur when multiple lawsuits involving the same or similar parties, legal issues, and factual issues are pending in the same court or in different courts within the state. The decision to consolidate is at the discretion of the court, which will consider factors such as the risk of prejudice to any party, the convenience of the parties, witnesses, and the promotion of the expeditious handling of the cases. If the cases are in different courts, one may be transferred to another court for consolidation. In the federal system, Rule 42 of the Federal Rules of Civil Procedure allows for similar consolidation when cases involve common questions of law or fact, and federal courts have the discretion to transfer cases between districts for consolidation under 28 U.S.C. § 1404(a) if it is in the interest of justice and for the convenience of parties and witnesses.