Every lawsuit has two core roles: the plaintiff, who brings the case, and the defendant, who must answer it. The terms show up in civil disputes, criminal prosecutions, and even the case name printed on a court filing, and mixing them up can make it hard to follow what's actually happening in a case.
A plaintiff files the complaint and carries the burden of proof, while a defendant responds and risks a default judgment if they don't. Case names list the plaintiff first, criminal cases replace the plaintiff with the State or the People, and other systems use different terms, like claimant, pursuer, or appellant. A defendant can even counter-sue as a counter-plaintiff, and class actions need a lead plaintiff to represent everyone else.
The plaintiff-versus-defendant distinction sounds simple, but it carries real procedural weight: who has to prove what, what a case gets called, and what happens if someone doesn't respond. Understanding it also sets up the next question for anyone named a defendant: what happens before trial even starts.
What Is the Difference Between a Plaintiff and a Defendant?
The main difference between a plaintiff and a defendant is that the plaintiff brings a civil claim against the defendant, while the defendant responds to and defends against that claim. In a typical lawsuit, the plaintiff starts the action by filing a complaint that states the claims and requested relief. The defendant may answer the complaint, file an authorized motion, assert defenses, and bring counterclaims.
Trial-court case captions generally identify the plaintiff and defendant, often in a Plaintiff v. Defendant format. In Smith v. ABC Corp., for example, Smith is the plaintiff and ABC Corp. is the defendant if Smith sued ABC Corp.
These labels can change with the proceeding. An appeal commonly uses terms such as appellant and appellee, while certain proceedings use petitioner and respondent. A defendant who files a counterclaim becomes a counterclaimant for that claim, and the plaintiff becomes the counterdefendant.
Who Is the Plaintiff in a Lawsuit?
The plaintiff is the party that brings a civil claim against another party and asks a court for legal or equitable relief. A plaintiff may be an individual, business, government body, organization, or other party with the legal capacity to sue under the applicable law.
A plaintiff typically initiates an ordinary civil action by filing a complaint with the court. The complaint identifies the parties, states the factual and legal basis for the claims, and specifies the relief sought.
A lawsuit can have more than one plaintiff or defendant. Courts may therefore identify parties as plaintiffs, defendants, co-plaintiffs, co-defendants, third-party plaintiffs, or third-party defendants depending on their roles.
The word plaintiff derives from Anglo-French and historically refers to a person who complains or brings a grievance before a court.
What Is the Plaintiff's Burden of Proof?
A plaintiff generally must prove each required element of a civil claim by the applicable standard of proof. The most common standard in U.S. civil cases is preponderance of the evidence, which means the fact is more likely true than not.
Preponderance of the evidence is sometimes described as requiring greater than a 50 percent probability, but the legal test is whether the evidence makes the proposition more likely true than not.
Not every civil claim uses the preponderance standard. Some claims or issues require clear and convincing evidence or another standard established by law.
The plaintiff also does not necessarily carry every burden in the lawsuit. A defendant may bear the burden of proving certain affirmative defenses, counterclaims, or other issues. The applicable substantive and procedural law determines which party bears each burden.
Civil standards of proof generally impose a lower evidentiary threshold than the beyond-a-reasonable-doubt standard required for a criminal conviction.
Who Is the Defendant in a Lawsuit?
The defendant is the party against whom a civil claim is brought and who may contest the plaintiff's allegations, claims, and requested relief. A defendant may be an individual, business, government body, organization, or other party that can be sued under applicable law.
After receiving legally sufficient service, a defendant generally has a specified period to respond under the applicable court rules. The exact deadline depends on the jurisdiction, type of case, method of service, and other procedural circumstances.
A response does not always mean filing an answer immediately. Depending on the governing rules, a defendant may file an answer, move to dismiss, challenge jurisdiction or service, assert affirmative defenses, bring counterclaims, or take other permitted procedural actions.
What Happens If a Defendant Does Not Respond to a Lawsuit?
A defendant who fails to respond within the applicable deadline risks entry of default and, potentially, a default judgment. Default does not automatically mean the plaintiff immediately wins the entire case.
The plaintiff generally must follow the applicable procedure for obtaining an entry of default and, when required, a default judgment. The court may require the plaintiff to establish entitlement to the requested relief and prove damages or other matters before entering judgment.
A default judgment can impose enforceable legal consequences against the defendant. Depending on the jurisdiction and circumstances, a defendant may ask the court to set aside an entry of default or default judgment when the applicable legal requirements are satisfied.
What Are the Common Types of Defendants?
Common defendants in civil lawsuits include individuals, businesses, corporations and other organizations, and government entities. A defendant is any party against whom the plaintiff asserts a legal claim, so the type of defendant depends on the facts and legal basis of the lawsuit.
- Individuals: A person can be sued for conduct that allegedly causes another party injury or loss. For example, a driver may be named as a defendant in a lawsuit arising from a car crash.
- Businesses and other organizations: Corporations, limited liability companies, partnerships, and other legal entities can be defendants. Claims may involve defective products, unsafe premises, contracts, employment disputes, or conduct for which an organization may be directly or vicariously liable.
- Government entities and officials: Federal, state, and local government bodies and, in some circumstances, government officials can be defendants. These lawsuits may be subject to sovereign or governmental immunity, notice requirements, shorter filing deadlines, or other special procedural rules.
- Multiple defendants: A plaintiff can sue more than one defendant in the same action when the applicable procedural rules permit the claims and parties to be joined. Each defendant's potential liability depends on the claims, facts, defenses, and applicable law.
Is an Insurance Company a Defendant?
An insurance company is a defendant when a plaintiff asserts a legally permitted claim directly against the insurer, but an insurer is not automatically a defendant simply because it insures someone who has been sued. Whether an insurer can be named directly depends on the claim and applicable jurisdiction.
In many liability lawsuits, the insured person or business remains the named defendant while an insurance company provides or pays for the legal defense under the insurance policy. The insurer may also pay a settlement or judgment up to applicable policy limits, subject to the policy's terms, exclusions, and coverage.
For example, after a car crash, the injured plaintiff may sue the allegedly negligent driver rather than the driver's insurance company. The driver's insurer may hire or pay defense counsel and cover an eligible settlement or judgment without becoming a named defendant in the underlying lawsuit. The insurer's involvement in defending or paying the claim does not, by itself, change the parties identified in the lawsuit.
What Happens When a Defendant Files a Counterclaim Against the Plaintiff?
A counterclaim is a claim asserted against an opposing party, so a defendant can assert a counterclaim against the plaintiff within the existing lawsuit. The defendant becomes the counterclaimant for that claim, while the plaintiff becomes the party defending against the counterclaim.
Under Federal Rule of Civil Procedure 13, counterclaims can be compulsory or permissive. A compulsory counterclaim generally arises from the same transaction or occurrence as the opposing party's claim and, subject to Rule 13's exceptions, must be stated in the pleading. A permissive counterclaim is a counterclaim against an opposing party that is not compulsory.
What Is the Difference Between a Counterclaim and a Crossclaim?
The main difference between a counterclaim and a crossclaim is that a counterclaim is asserted against an opposing party, while a crossclaim is asserted against a coparty.
For example, a defendant may assert a counterclaim against the plaintiff. One defendant may instead assert a crossclaim against a co-defendant when Federal Rule of Civil Procedure 13(g)'s requirements are satisfied.
A Rule 13(g) crossclaim generally must arise from the same transaction or occurrence as the original action or a counterclaim, relate to property involved in the original action, or assert qualifying liability by a coparty.
How Does the Case Name Order Work for Plaintiff vs Defendant?
Civil trial-court case captions generally list the plaintiff first and the defendant second in a Plaintiff v. Defendant format. The plaintiff is the party bringing the claim, while the defendant is the party against whom the claim is brought.
For example, Brown v. Board of Education of Topeka identifies Brown on the plaintiff side and the Board of Education on the defendant side. The consolidated Supreme Court case involved multiple plaintiffs, although Oliver Brown's surname became the name used in the case caption.
Case-name order becomes more complicated on appeal. The parties may be described as the appellant and appellee or, in some jurisdictions, the petitioner and respondent. Depending on the court and citation rules, the case may retain a caption based on the original parties rather than simply reversing the names when the original defendant appeals. For this reason, the first name in an appellate case citation does not always identify the original plaintiff.
How Are Criminal Cases Named?
Criminal case captions generally name the prosecuting government first and the accused defendant second. The exact government designation depends on the jurisdiction.
U.S. federal criminal cases commonly use United States v. Defendant. State criminal cases may use captions such as State v. Defendant, People v. Defendant, or Commonwealth v. Defendant, depending on the state.
Several Commonwealth jurisdictions use R v Defendant, with R representing the Crown. The R stands for Rex during the reign of a king and Regina during the reign of a queen.
How Is a Real Party in Interest Determined for Plaintiff vs Defendant?
The real party in interest is the person or entity entitled under the governing substantive law to enforce the right asserted in the lawsuit. The inquiry focuses on who possesses the right being enforced, rather than simply whose name appears in the case caption.
In U.S. federal civil cases, Federal Rule of Civil Procedure 17(a)(1) requires an action to be prosecuted in the name of the real party in interest. Determining that party therefore requires identifying the substantive right at issue and determining who is legally entitled to enforce it.
Rule 17(a)(1) also allows certain parties to sue in their own names without joining the person for whose benefit the action is brought. These parties include:
- an executor
- an administrator
- a guardian
- a bailee
- a trustee of an express trust
- a party with whom or in whose name a contract was made for another's benefit
- a party authorized by statute
Rule 17(a)(3) also protects against immediate dismissal when an action is not initially prosecuted in the name of the proper party. A court must allow a reasonable time for the real party in interest to ratify, join, or be substituted into the action after an objection.
The real-party-in-interest requirement is distinct from standing. Standing concerns whether a party has the legal entitlement required to invoke the court's authority, while the real-party-in-interest inquiry concerns who possesses the substantive right being enforced.
How Does Plaintiff vs Defendant Terminology Differ in Criminal Cases?
In a typical U.S. civil case, the party asserting a claim is the plaintiff, while in a criminal case the government prosecutes the defendant. The formal name of the prosecuting government varies by jurisdiction.
Federal criminal cases generally identify the prosecuting party as the United States. State prosecutions may be brought in names such as the State, the People, or the Commonwealth, depending on the jurisdiction. The term prosecution generally refers to the government side conducting the criminal case rather than the formal party name.
| Aspect | Civil case | Criminal case |
|---|---|---|
| Party bringing the action | Plaintiff | Government, such as the United States, State, People, or Commonwealth |
| Party responding to the action | Defendant | Defendant |
| Nature of action | Private or governmental civil claim | Government prosecution for an alleged crime |
| Usual ultimate burden of proof | Preponderance of the evidence for many civil claims | Beyond a reasonable doubt for each element of the charged offense |
| Potential result | Damages, injunction, declaratory relief, or other civil remedies | Acquittal or conviction, with criminal penalties following a conviction |
The term defendant is commonly used in both civil and criminal trial proceedings. A civil plaintiff seeks a civil remedy against a defendant. In a criminal prosecution, the government charges and prosecutes the defendant for an alleged criminal offense.
What Are the Types of Party Terminology Alternatives to Plaintiff and Defendant?
Alternatives to plaintiff and defendant include claimant and respondent, petitioner and respondent, appellant and appellee, applicant and respondent, and pursuer and defender. Courts use different party names based on the jurisdiction, type of proceeding, and procedural stage of the case.
These terms do not always function as exact synonyms for plaintiff and defendant. Some identify which party initiated a particular proceeding, while others identify a party's role on appeal or within a specialized legal process.
| Proceeding or jurisdiction | Party bringing or challenging the matter | Opposing party |
|---|---|---|
| Typical U.S. civil lawsuit | Plaintiff | Defendant |
| England and Wales civil claim | Claimant | Defendant |
| Scottish civil action | Pursuer | Defender |
| Many petitions | Petitioner | Respondent |
| Many applications | Applicant | Respondent |
| Many appeals | Appellant | Appellee or respondent |
| U.S. criminal prosecution | Government | Defendant |
What Is a Claimant Versus a Plaintiff?
A claimant asserts a claim or entitlement, while a plaintiff is generally the party who brings a civil lawsuit in a court system that uses plaintiff terminology. Whether a party is called a claimant or plaintiff depends on the jurisdiction and type of proceeding.
England and Wales adopted claimant in place of plaintiff under the Civil Procedure Rules 1998, which came into force on April 26, 1999. A person bringing a civil claim governed by those rules is therefore generally called the claimant, while the opposing party is the defendant.
Scotland uses different civil terminology. The party bringing a civil action is traditionally called the pursuer, while the party against whom the action is brought is the defender.
The United States also uses the term claimant, so the term is not restricted to claims made outside court. Claimant commonly describes a person or entity asserting a right to money, property, benefits, insurance coverage, or other relief in particular legal and administrative proceedings.
A person may therefore be a claimant without being a plaintiff. The correct term depends on the proceeding and the rules governing it.
What Is a Petitioner Versus a Respondent?
A petitioner is a party who asks a court or tribunal for a particular order or form of relief, while the respondent is the party who responds to that request. Petitioner and respondent terminology appears in various specialized proceedings and appeals.
What Is an Appellant Versus an Appellee?
An appellant is the party seeking appellate review of a lower court's decision, while the appellee is the party responding to the appeal. Some courts use respondent instead of appellee.
Either the original plaintiff or defendant can become the appellant. Appellant and appellee therefore identify appellate roles rather than the parties' original positions in the lawsuit.
For example, if a defendant loses at trial and appeals the judgment, the defendant becomes the appellant and the original plaintiff generally becomes the appellee. If the plaintiff appeals an adverse judgment, the plaintiff becomes the appellant and the defendant generally becomes the appellee.
An appellant may seek reversal, vacatur, modification, or remand, depending on the issue and available appellate remedy. Some courts and proceedings use petitioner and respondent instead of appellant and appellee.
What Is an Applicant Versus a Respondent?
An applicant requests relief through an application, while a respondent answers or opposes that application. Courts, tribunals, and other decision-makers use this terminology in various specialized proceedings.
What Is a Pursuer Versus a Defender?
In Scottish civil procedure, a pursuer is generally the party bringing the action, while a defender is the party against whom the action is brought. Their roles are broadly comparable to plaintiff and defendant, but pursuer and defender are the jurisdiction-specific terms.
What Are the Parties Called in Bankruptcy?
Bankruptcy proceedings commonly use specialized terms such as debtor, creditor, trustee, and claimant rather than relying exclusively on plaintiff and defendant. A debtor is generally the person or entity that is the subject of the bankruptcy case, while a creditor generally holds a claim against the debtor.
Bankruptcy cases can also contain separate lawsuits called adversary proceedings. These proceedings generally use plaintiff and defendant terminology, so those terms do not disappear entirely from bankruptcy practice.
Who Is the Lead Plaintiff in a Class Action Plaintiff vs Defendant Case?
A federal class action is brought by one or more named plaintiffs who seek to represent a larger class, but Rule 23 does not require every class action to have a single party formally designated as the lead plaintiff. The named plaintiffs must satisfy the requirements for class certification and adequately represent the proposed class.
Federal Rule of Civil Procedure 23(a) establishes four threshold requirements:
- Numerosity: The class must be so numerous that joining every member individually is impracticable.
- Commonality: Questions of law or fact must be common to the class.
- Typicality: The representative parties' claims or defenses must be typical of the class's claims or defenses.
- Adequacy: The representative parties must fairly and adequately protect the interests of the class.
The proposed class must also satisfy at least one category under Rule 23(b). Class counsel is addressed separately under Rule 23(g), which requires the court to appoint counsel when it certifies a class.
Who Is the Lead Plaintiff in a Securities Class Action?
The Private Securities Litigation Reform Act of 1995 establishes a specific process for appointing a lead plaintiff in certain federal private securities class actions. The court applies a rebuttable presumption to identify the most adequate plaintiff.
The presumptively most adequate plaintiff is generally the person or group that filed the complaint or timely moved for appointment, has the largest financial interest in the relief sought by the class, and otherwise satisfies Rule 23's requirements. The largest financial interest matters, but it does not automatically determine who becomes lead plaintiff.
How Does Plaintiff vs Defendant Play Out in a Real Lawsuit Example?
Consider a driver injured in a crash who alleges that another driver negligently ran a red light: the injured driver may become the plaintiff, while the allegedly negligent driver becomes the defendant. Filing the lawsuit establishes their procedural roles, not the defendant's liability.
The plaintiff may seek compensation for recoverable losses such as medical expenses, lost income, property damage, and pain and suffering, depending on the facts and applicable law.
The defendant can deny negligence, dispute causation or damages, assert affirmative defenses, and present evidence in defense of the claim. The plaintiff generally must prove the required elements of the negligence claim by the applicable standard of proof.
How Does Understanding Plaintiff vs Defendant Connect to Pretrial Release?
Plaintiff-versus-defendant terminology identifies the parties to a case, while pretrial release determines whether and under what conditions a criminal defendant remains free or detained while criminal charges are pending. Pretrial release therefore concerns criminal procedure rather than the ordinary plaintiff-defendant relationship in a civil lawsuit.
A civil defendant ordinarily does not face detention merely because someone files a civil lawsuit against them. In a criminal case, however, a defendant who has been arrested or brought before the court may face a separate decision concerning release, detention, bail, or conditions imposed while the case is pending.
The specific process varies by jurisdiction and case. Depending on the governing law, a court may release a defendant without monetary bail, impose conditions of release, require bail or a bond where permitted, or order pretrial detention when the legal requirements for detention are satisfied.
A pretrial release or detention decision does not determine whether the defendant is guilty. It determines the defendant's custody or release status while the criminal case proceeds.