If two claims are unrelated, can they be joined in a federal court case?

In federal court, the ability to join claims is governed by the Federal Rules of Civil Procedure, specifically Rule 18. This rule allows a party to assert multiple claims against an opposing party in one action. However, the requirement for joinder of claims is that they must arise from the same transaction or occurrence, or be part of a common nucleus of operative fact.

The selected answer aligns with this requirement. If two claims are unrelated, meaning they do not share a transaction, occurrence, or any significant factual connection, they cannot be joined in a single federal court case. Each claim must be filed separately unless they meet the joinder criteria based on their relationship to one another.

While there may be procedural mechanisms such as consolidation for related claims, that does not apply to claims that do not relate to each other in the required ways. Other options suggest various justifications for joining unrelated claims, but these are not consistent with the rules governing joinder. For example, merely having one claim that is based in federal law does not give rise to the ability to join an unrelated claim; both claims must still meet the criteria laid out in the rules. Thus, the principle established by the rules is clear: unrelated claims cannot be joined together in federal court.