An appellant is the party who brings an appeal, asking a reviewing court to change or set aside a decision made in a lower court. The name describes that party’s role in the appeal; it does not automatically mean plaintiff, defendant, or the person who lost every issue in the original case.

In plain English, the appellant says, “This decision contains an error that justifies a different result.” The opposing party, usually called the appellee or respondent, answers the appeal. These roles concern the particular decision being reviewed, rather than who originally sued whom. The Third Circuit’s definitions describe an appellant as seeking reversal or modification and an appellee as generally seeking to uphold the decision.

How to identify the appellant

Start with the document that initiates the appeal and the court’s identification of the parties. Do not assume the first name in a case caption is the appellant: a caption may retain the order of names used in the trial court.

1. Find the filing that seeks review. A notice of appeal normally identifies the party taking the appeal. In some proceedings, the initiating document is a petition for review or a request for permission to appeal.
2. Identify the challenged decision. Look for the judgment, order, or specific part of a decision that the party wants reviewed. Asking to change that ruling is more useful for identifying the role than asking who “won the case.”
3. Check the appellate docket and caption labels. They may identify a party as plaintiff-appellant, defendant-appellant, respondent, or cross-appellant. Read both parts of a combined label: one describes the earlier role and the other describes the current proceeding.
4. Check for a cross-appeal or a different review procedure. Both sides may seek changes, and the court’s rules may determine how they are designated for briefing.

For an appeal as of right from a federal district court, Federal Rule of Appellate Procedure 3 requires the notice to identify the parties taking the appeal, the judgment or appealable order, and the court to which the appeal is taken. Rule 12 provides for docketing under the district-court action’s title while identifying the appellant. These are federal rules, not a universal filing procedure for every state court. See the current Federal Rules of Appellate Procedure, Rules 3 and 12.

Appellant, appellee, respondent, and trial-court roles

The same person can have different labels as a case moves between courts. “Plaintiff-appellant” means the plaintiff below is now bringing the appeal; “defendant-appellant” means the defendant below is doing so.

The federal courts commonly use appellee for the responding party. California’s Court of Appeal uses respondent, as its appeals glossary explains. “Respondent” also appears in other proceedings, so the word alone does not establish whether a case is an appeal. The actual court and type of filing matter.

Civil and criminal examples

These hypothetical examples show how a trial-court role becomes an appellate role. They assume a legally available appeal, not that every ruling can be appealed immediately.

Civil plaintiff appeals. Morgan sues a contractor for breach of contract, but the court enters judgment for the contractor. Morgan brings an appeal challenging that judgment. Morgan is the plaintiff-appellant; the contractor is the defendant-appellee, or respondent in a court using that label.

Criminal defendant appeals. A defendant convicted at trial brings an appeal arguing that a legal error affected the conviction. The defendant is the appellant, and the government responds. Bringing the appeal does not erase the conviction or establish that the alleged error occurred. The reviewing court must decide the issues properly before it.

A party who won something still appeals an adverse part. A civil plaintiff obtains relief on one claim but receives an adverse ruling on a separate claim. If the applicable law allows that party to appeal the adverse ruling, the plaintiff can be the appellant on that issue. Calling the plaintiff the overall “winner” does not identify the appellate role or establish a right to appeal.

The U.S. Courts’ appeals overview explains that either side in a civil case may appeal, and a criminal defendant may appeal a guilty verdict. Criminal appeals have additional limits: the government cannot appeal an acquittal simply to obtain another chance to convict. Whether a particular party can appeal a particular order or sentence depends on the governing law.

What an appellant does during an appeal

An Appeal is a process for obtaining review of a decision. The appellant has to do more than disagree with it. The party must follow the court’s procedure and explain why the identified error warrants the relief requested.

The usual sequence is:

1. Initiate the appeal properly. File the required notice or other initiating document in the correct court within the applicable time. For federal district-court appeals as of right, Rule 3 directs filing with the district clerk within the time allowed by Rule 4. Permission-based appeals and other review routes have different requirements; there is no single deadline for every appeal.
2. Arrange the record required for review. The record supplies the materials from the proceedings below. Federal Rule 10 includes the original papers and exhibits, any transcript, and the certified docket entries. Transcript and record responsibilities depend on the rules and the issues being raised.
3. Submit the opening or principal brief. A brief is the written argument. Federal Rule 28 requires, among other things, the issues presented, relevant case history and record references, and the argument. The appellant connects the claimed error to a legal reason for changing the decision.
4. Address the response and any scheduled argument. The appellee or respondent answers; a reply may follow under the applicable rules. Some appeals are decided on briefs, while others include oral argument. Oral argument is not a new witness trial.
5. Receive the reviewing court’s decision. Depending on the case, the court may uphold the decision, change or reverse it, or return the matter for further proceedings. Procedural defects can also prevent a decision on the merits.

These federal record and briefing details are supported by Rules 10 and 28. The U.S. Courts overview describes written briefs, oral argument, and proceedings after an appellate decision. State procedures, local rules, and court orders must be checked separately.

Cross-appeals: when both sides seek a change

A responding party may also want a different part of the decision changed. A cross-appeal can create two sets of challenges. For example, a plaintiff appeals dismissal of one claim while the defendant appeals a separate award against it. Each party’s requested change must be distinguished from its response to the other party’s challenge.

California’s guidance on additional appeal filings explains that a respondent filing a cross-appeal also becomes an appellant and must follow the requirements for both roles. In federal cross-appeals, Rule 28.1 designates the party filing the first notice as appellant for that rule and Rules 30 and 34; same-day notices and changes by agreement or court order have specific provisions. That is a procedural designation for managing the appeal, not a declaration that only one side seeks review.

Is a petitioner the same as an appellant?

Both labels can describe a party seeking review, but they are not universally interchangeable. A court may use “petitioner” because the proceeding begins with a petition rather than a notice of appeal.

For example, Federal Rule 15 addresses review of agency orders: the petition names the parties seeking review, names the agency as respondent, and identifies the order or part to be reviewed. The governing statute determines the available review route. Some agency disputes begin with judicial review in a district court rather than directly in a court of appeals, as the U.S. Courts overview notes.

A petition asking a higher court to accept discretionary review is also different from an appeal that a party is entitled to bring. The label “petitioner” therefore needs the same context check: which court, which decision, and which review procedure?

Related terms in appeal documents

• Notice of appeal: The filing that identifies the party taking the appeal and the decision challenged under the applicable rules. It is not the full written argument.
• Brief: A written presentation of a party’s legal arguments. An opening brief presents the appellant’s challenge; a response answers it.
• Record on appeal: The materials from the proceedings below that the reviewing court uses. It is different from a party’s new account of what happened.
• Standard of review: The legal standard the appellate court applies when examining a particular issue. Different issues can receive different treatment; federal Rule 28 requires the appellant’s argument to state the applicable standard for each issue.
• Appellee or respondent: The party answering the appeal, with the label depending on the court and proceeding.
• Appellant or petitioner: A party seeking review, with the precise title depending on whether the procedure is an appeal or a petition. Read the court’s designation rather than assuming the labels are interchangeable.

These terms explain the documents’ function; they do not establish that an appeal is available or that the appellant has satisfied the rules.

Common misunderstandings

Is the appellant always the defendant? No. Either an original plaintiff or defendant may bring a civil appeal. “Defendant” describes the earlier case role; “appellant” describes the party seeking appellate review.

Is the appellant always the losing party? Usually the party is challenging an adverse decision, but “the loser” is too broad. A judgment can resolve several claims differently, and both sides can appeal. The appellant must still have a legally available basis to seek review; dissatisfaction by itself is insufficient.

Does becoming an appellant mean getting a second trial? No. An ordinary appeal reviews the decision and record under appellate rules rather than starting the case again with new testimony. The Ninth Circuit’s appeal-process guide explains that its appeals do not accept new evidence or testimony. Further trial-court proceedings may occur if the appellate court sends the case back.

Does the label show that the appeal will succeed? No. It identifies a procedural role. It says nothing by itself about the merits, whether the appeal is timely, or whether the court can hear it.

When reading a document, identify the party bringing the review proceeding, the decision challenged, and any cross-appeal. That combination explains the role more accurately than the order of names or a “winner versus loser” shorthand.