How can a party challenge the joinder of another party?

The correct approach for challenging the joinder of another party is through a motion to dismiss or for a more definite statement. This procedural mechanism allows a party to formally object to the inclusion of an additional party in the lawsuit, asserting that the joinder is improper under the applicable rules.

When a party believes that the requirements for proper joinder are not met—such as failing to satisfy the standards of commonality, complete diversity, or whether the claims are related—it can file a motion that formally presents these arguments to the court. This allows the court to evaluate the legitimacy of the joinder based on the relevant legal standards and determines whether the party should remain part of the action.

The other options do not effectively address the challenge to joinder. Appealing the court's previous decisions pertains to seeking review of earlier rulings, which typically comes into play after a ruling has been made, rather than contesting the presence of a party at an initial stage. Requesting a new trial also does not apply, as it is focused on the outcome of a completed trial rather than the procedural issues at the joinder stage. Informally notifying the opposing party lacks the formal structure necessary to invoke the court's authority or ensure a consistent record in the litigation proceedings.