A defendant who feels that the plaintiff in a lawsuit should have sued someone else on the claim can bring that other person into the case. The procedure for doing this is called IMPLEADER, and the additional party is called a third-party defendant. The original defendant who impleads a third-party defendant is called a third-party plaintiff, but he or she continues to be a defendant in relation to the plaintiff.
For example, a restaurant patron who becomes ill after eating a ham dinner can sue the restaurant. The patron is the plaintiff, and the restaurant is the defendant. The restaurant may want to implead the meat-packing company that furnished the ham, if it believes that the meat was tainted before it was delivered to the restaurant. The restaurant cannot avoid being a defendant, but it can cover itself by impleading the meat packer and making that company a third-party defendant. If a jury finds that the ham was bad and that the patron is entitled to $10,000 damages, then the restaurant has an opportunity to show that its employees were not careless in preparing or serving the meat and that the restaurant should not be liable for the damages.
The decision to allow impleading of a third party is within the discretion of the court. The court also decides whether the third-party defendant may file claims against any of the other parties or whether the other parties may make additional claims against the third-party defendant. Permitting all parties to put forward all their claims in one action promotes efficient use of the courts, but a court will not permit additional parties or claims to complicate proceedings, delay resolution of the main controversy, or confuse a jury.
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