Definition
A plaintiff is the party who begins a civil lawsuit by filing a complaint against another party, alleging that the other party caused them legal harm. The plaintiff asks the court to provide a remedy—most often money damages, but sometimes an injunction or other order. Because the plaintiff is the one seeking relief, the plaintiff carries the burden of proving the claims that the lawsuit is built on.
Legal Meaning
The plaintiff is the moving party in civil litigation—the person, business, or other entity that sets the case in motion. By filing the complaint, the plaintiff frames the dispute, identifies the legal claims (called causes of action), and tells the court what relief they want. Everything that follows in the lawsuit responds, in some way, to the plaintiff's allegations.
This role exists in civil cases, not criminal cases. In a criminal prosecution, the government (the state or the United States) brings the case against an accused person, and the accusing party is called the prosecution rather than the plaintiff. The person accused of the crime is the defendant in both settings, but only civil cases have a plaintiff. For more on how these systems differ, see our guide on civil vs. criminal cases.
Because the plaintiff is asking the court to act, the law places the burden of proof on the plaintiff. In most civil cases, that burden is the preponderance of the evidence—meaning the plaintiff must show their version of events is more likely true than not. The plaintiff also must establish that the court has authority over the dispute, an issue of jurisdiction, and must file within the applicable statute of limitations.
Key Points
- The plaintiff is the party who starts a civil lawsuit by filing a complaint
- Plaintiffs seek a remedy such as money damages, an injunction, or a declaratory judgment
- The plaintiff carries the burden of proof and must prove each element of the claim
- A plaintiff can be an individual, a business, an organization, or a government agency
- In criminal cases, the accusing party is the prosecution, not a plaintiff
- Multiple plaintiffs can join one suit, and class actions let a few represent many
- The plaintiff must sue within the statute of limitations or risk dismissal
- If a defendant files a counterclaim, the original plaintiff becomes a defendant on that claim
Real-World Example
Maria slips on an unmarked wet floor in a grocery store and breaks her wrist. After the store refuses to cover her medical bills, Maria files a lawsuit against the store. In that lawsuit, Maria is the plaintiff and the grocery store is the defendant.
As the plaintiff, Maria must prove that the store owed her a duty of care, breached that duty by leaving a hazard unmarked, and caused her injury. If the jury finds it more likely than not that the store's negligence caused her broken wrist, Maria—the plaintiff—wins and may recover damages for her medical bills, lost wages, and pain and suffering.
Plaintiff vs. Defendant: Roles Compared
| Aspect | Plaintiff | Defendant |
|---|---|---|
| Starts the case | Yes — files the complaint | No — responds with an answer |
| Burden of proof | Carries it (usually preponderance) | Defends; may raise affirmative defenses |
| Goal | Obtain a remedy or relief | Avoid or reduce liability |
| Order of presentation | Presents evidence first at trial | Presents after the plaintiff rests |
| Title on appeal | Appellant or appellee, depending | Appellant or appellee, depending |
The Plaintiff's Role Through the Case
A plaintiff's involvement runs through every stage of litigation:
Filing and Pleadings
The case begins when the plaintiff files the complaint and arranges for the defendant to be served. The complaint must state a recognized legal claim and request specific relief.
Discovery
During discovery, the plaintiff gathers and exchanges evidence, answers written questions, produces documents, and may sit for a deposition. The plaintiff also requests information from the defendant to build the case.
Trial and Judgment
At trial, the plaintiff presents evidence first because they bear the burden of proof. If the plaintiff succeeds, the court enters a judgment in their favor. If the plaintiff fails to meet the burden, the case may be dismissed or resolved by summary judgment before trial.
Related Terms
Thinking About Filing a Claim?
If you believe you have been harmed, an experienced attorney can tell you whether you have a case and how to bring it.
Find a Lawyer Near YouWhen You Need a Lawyer
If you are considering becoming a plaintiff, you should speak with an attorney early. A lawyer can help you:
- Evaluate whether your situation supports a valid legal claim
- Identify the correct defendants and the proper court
- Draft a complaint that states each element of your claim
- Gather and preserve the evidence you will need to meet your burden of proof
- File before the statute of limitations expires
Many personal injury attorneys work on a contingency fee, meaning you owe no fee unless they recover money for you. To understand how legal costs work, see our guide on understanding legal fees.
Frequently Asked Questions
What is the difference between a plaintiff and a defendant?
The plaintiff is the party who starts a civil lawsuit by filing a complaint and asking the court for a remedy, such as money damages or an injunction. The defendant is the party being sued and must respond to the plaintiff's allegations. The plaintiff carries the burden of proving the claims, while the defendant defends against them.
What does a plaintiff have to prove?
In most civil cases, the plaintiff must prove each element of their claim by a preponderance of the evidence, meaning it is more likely than not that their version of events is true. For certain claims, such as fraud, a higher standard of clear and convincing evidence may apply. The plaintiff bears this burden because they are the party asking the court to act.
Can a plaintiff be a company or organization?
Yes. A plaintiff can be an individual, a business, a nonprofit, a government agency, or any other entity that the law recognizes as capable of bringing suit. In a class action, a small group of named plaintiffs may represent a much larger group of similarly situated people who share the same legal claim.
Does a plaintiff need a lawyer to file a lawsuit?
Individuals can represent themselves, which is called appearing pro se, but it is rarely advisable for complex cases. In most courts, corporations and other entities must be represented by a licensed attorney. Because the plaintiff bears the burden of proof and must follow strict procedural rules, hiring a lawyer significantly improves the chances of success.
Who pays the costs when a plaintiff loses?
Under the American rule that applies in most U.S. courts, each side generally pays its own attorney fees regardless of who wins. A losing plaintiff may still be ordered to pay certain court costs, and some statutes or contracts allow the prevailing party to recover fees. Many personal injury plaintiffs use a contingency fee arrangement so they owe no fee unless they recover.