Lawsuit

===Appeal===
{{Main|Appeal}}
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After a final decision has been made, either party or both may [[appeal]] from the judgment if they believe there had been a procedural error made by the trial court. It is not necessarily an automatic appeal after every judgment has been made, however, if there is a legal basis for the appeal, then one has the right to do so. The prevailing party may appeal, for example, if they wanted a larger award than was granted. The [[appellate court]] (which may be structured as an intermediate appellate court) and/or a higher court then affirms the judgment, declines to hear it (which effectively affirms it), reverses—or vacates and remands. This process would then involve sending the lawsuit back to the lower trial court to address an unresolved issue, or possibly request for a whole new trial. Some lawsuits go up and down the appeals ladder repeatedly before final resolution.

The appeal is a review for errors rather than a new trial, so the appellate court will defer to the discretion of the original trial court if an error is not clear. The initial step in making an appeal consists of the petitioner filing a notice of appeal and then sending in a brief, a written document stating reason for appeal, to the court. Decisions of the court can be made immediately after just reading the written brief, or there can also be oral arguments made by both parties involved in the appeal. The appellate court then makes the decision about what errors were made when the law was looked at more closely in the lower court. There were no errors made, the case would then end, but if the decision was reversed, the appellate court would then send the case back down to the lower court level. There, a new trial will be held and new information taken into account.

Some jurisdictions, notably the United States, but prevalent in many other countries, prevent parties from relitigating the facts on appeal, due to a history of unscrupulous lawyers deliberately reserving such issues in order to ambush each other in the appellate courts (the "invited error" problem). The idea is that it is more efficient to force all parties to fully litigate all relevant issues of fact before the trial court. Thus, a party who does not raise an issue of fact at the trial court level generally cannot raise it on appeal.

When the lawsuit is finally resolved, or the allotted time to appeal has expired, the matter is ''[[res judicata]]'', meaning the plaintiff may not bring another action based on the same claim again. In addition, other parties who later attempt to re-litigate a matter already ruled on in a previous lawsuit will be ''[[Estoppel|estopped]]'' from doing so.