A civil lawsuit is an adversary proceeding between (or among) two or more parties who have competing interests. Let's start with the basics. The party who brings the suit to court is called the plaintiff. The party sued by the plaintiff is called the defendant.
A defendant who has a claim against the plaintiff can bring what is known as a counterclaim, and at that point the defendant becomes what is known as the "counter-plaintiff" with respect to the counterclaim against the plaintiff (who is now also known as the "counter-defendant").
If that's not confusing enough, when the defendant or counter-defendant believes that a third party may be legally responsible for the claim asserted against them by the plaintiff, the defendant may bring that third party into the lawsuit as a third-party defendant. Ideally, each civil lawsuit will include all parties who may potentially be needed to award complete relief, so that multiple proceedings are avoided. (Learn more about Pleadings and Motions in a Civil Case.)
Are the Proper Parties Named?
It is important to have the proper parties named in a civil lawsuit. Courts require that civil lawsuits be brought by "the real party in interest", which means that the party bringing suit is legally entitled to seek the relief requested. In the case of a minor, suit must be brought by someone of legal age who has the authority to sue on the minor's behalf; this is typically a person who serves as the minor's guardian or "next friend." In the case of an incompetent person, suit must be brought by that person's court-appointed guardian. If the person bringing suit cannot establish his or her legal capacity to do so, the suit will be dismissed.
Issues may arise with respect to the naming of the proper party or parties when a plaintiff sues a company as opposed to an individual. For example, a company may be doing business under a certain name, but that name may not be the same as the entity responsible for the claim (e.g., ABC Corporation, doing business as Acme Auto Parts). In these cases, the plaintiff must research the local and state company registration databases to determine the name of the entity that is legally liable, because a suit brought against an entity that bears no legal liability will be dismissed.
Parties and the "Burden of Proof"
Once all of the necessary parties are joined in the lawsuit, the case proceeds with pre-trial discovery and other proceedings preliminary to the trial itself.
The plaintiff, as the moving party, bears the "burden of proof" on all of the elements of its claims. In a civil case, this burden of proof requires the plaintiff to establish its case by a "preponderance of the evidence," which means that the finder of fact (i.e., the jury, or the judge in a non-jury trial) must conclude that the scales tip more than 50-50 in the plaintiff's favor.
The defendant has no burden of proof (except as it pertains to any affirmative defenses raised in response to the plaintiff's claims) but as a practical matter the defendant must persuade the finder of fact that the plaintiff's claim lacks merit. If it fails to do so, the plaintiff can be expected to prevail.
Parties and Trial Procedure
At trial, the plaintiff proceeds first in the presentation of evidence by way of witness testimony and the introduction of exhibits. When the plaintiff rests its case, the defendant is afforded the opportunity to offer its own witnesses and exhibits. The plaintiff then has the chance to put in its rebuttal to the defendant's case, and in that way the plaintiff is said to have the "last word" at trial.
When all the evidence has been received, the attorneys for both the plaintiff and defendant are allowed to present closing arguments that summarize the evidence and argue for a verdict in their client's favor. The ultimate decision as to who wins and who loses is then placed in the hands of the jury or the judge.
If the trial court verdict is appealed, the party who files the appeal is known as the "appellant" and the opposing party is known as the "appellee." Learn more about Appeals and Standards of Review.