A person can volunteer to become a party in a lawsuit by a procedure called intervention. A person might wish to intervene in a lawsuit if he or she has an interest that will be affected by the outcome of the case and the person believes that this interest will not be adequately protected by the other parties.
A court decides whether to permit an intervening party by BALANCING the interests of the person seeking to intervene with the additional burden imposed on the existing parties if the person is allowed to enter the lawsuit. The court considers whether the intervenor is raising the same issues already present in the case or whether the intervenor is seeking to inject new controversies into the case. The intervenor must demonstrate some practical effect of the outcome of the case on his or her rights or property. If a person is not allowed to intervene, the person is not bound by the judgment given in the case.
An intervenor must make the request to intervene in a motion to the court. Timing is important. If the case has already progressed beyond the preliminary stages, the court is likely to find that the intervenor's intrusion would prejudice the rights of the existing parties, which would be grounds for the court to deny the motion.
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