The difference between a complainant and a plaintiff comes down to who runs the case. A plaintiff is the person or entity that files a civil lawsuit asking a court for money or an order against someone else. A complainant is someone who reports a crime to law enforcement or files a formal grievance with a government agency. The plaintiff drives their own case and can settle or walk away. The complainant hands the matter to the government and loses most control over what happens next.
Both roles start a legal process. The rights, costs, and power attached to each are not the same.
Who Controls the Case
This is the practical gap that matters most. A plaintiff can negotiate a settlement, voluntarily dismiss the lawsuit, or change strategy at almost any point. Before the defendant files an answer or a motion for summary judgment, the plaintiff can drop the case simply by filing a notice with the court. After that, dismissal needs a court order or a signed agreement from all parties.1Legal Information Institute. Rule 41 – Dismissal of Actions
A criminal complainant has no such power. Once the government takes on the prosecution, only the prosecutor can decide to dismiss the charges, and even then the prosecutor needs the court’s permission.2Legal Information Institute. Federal Rules of Criminal Procedure Rule 48 – Dismissal If a complainant later decides they don’t want to cooperate, the government can issue a subpoena compelling their testimony, and ignoring it can bring contempt of court.3Legal Information Institute. Federal Rules of Criminal Procedure Rule 17 – Subpoena People often assume a crime victim can “drop the charges.” They can’t. That decision belongs to the prosecutor.
What a Plaintiff Does
A plaintiff opens a civil case by filing a complaint with the court and serving a copy on the defendant.4United States Courts. Civil Cases The complaint lays out what the defendant allegedly did and what remedy the plaintiff wants. In federal court, the filing fee is $405 (a $350 statutory fee plus a $55 administrative fee) just to get started.5Office of the Law Revision Counsel. 28 USC 1914 – District Court Filing Fees State court fees vary but often land in a similar range.
Once filed, the plaintiff carries the burden of proof. In most civil cases that means meeting the “preponderance of the evidence” standard, which is showing the claim is more likely true than not.6Legal Information Institute. Preponderance of the Evidence If the plaintiff clears that bar, a court can award compensatory damages covering actual losses like medical bills and lost income.7Legal Information Institute. Compensatory Damages The plaintiff can also ask for injunctive relief, which is a court order forcing the defendant to do something or stop doing something.8Legal Information Institute. Injunctive Relief
Filing a lawsuit also opens the plaintiff to discovery. The defendant can demand witness information, documents, a breakdown of claimed damages, and details about insurance that might cover a judgment.9Legal Information Institute. Rule 26 – Duty to Disclose; General Provisions Governing Discovery Discovery is where most of the time and expense in civil litigation lives.
What a Criminal Complainant Does
In criminal law, the complainant is the person who reports an alleged crime. Often that’s the victim. The complainant typically signs a sworn statement describing what happened, and a judge reviews it to decide whether probable cause exists to proceed.10Legal Information Institute. Criminal Complaint That affidavit can form the foundation of a criminal complaint. From that point on, the complainant is not in charge. The government — through a district attorney at the state level or a U.S. Attorney in federal court — takes over as the prosecuting party.11Offices of the United States Attorneys. About the U.S. Attorneys Offices
The complainant becomes a witness for the prosecution, not a party to the case. They may testify, provide evidence, and cooperate with investigators, but they don’t choose the charges, negotiate a plea, or set the trial date. The case caption reads “United States v. Smith” or “State v. Smith.” The complainant’s name doesn’t appear, because the crime is treated as an offense against the public.
Rights at Sentencing
Complainants don’t run the prosecution, but they do have a voice at sentencing. A victim impact statement lets the complainant describe the physical, emotional, and financial harm they suffered. The judge reads written statements before sentencing and can also hear the complainant speak in court.12Department of Justice. Victim Impact Statements The statement also includes a financial loss breakdown the judge uses when deciding whether to order restitution, which is money the defendant pays directly to the victim for crime-related expenses.
Federal law gives crime victims a set of specific protections. Under the Crime Victims’ Rights Act, a complainant has the right to be reasonably heard at proceedings involving release, plea deals, and sentencing, to confer with the prosecutor, to receive timely notice of court proceedings, and to full restitution as provided by law.13Office of the Law Revision Counsel. 18 U.S. Code 3771 – Crime Victims Rights These rights don’t put the complainant in control; they guarantee a seat at the table.
Complainants in Administrative Proceedings
“Complainant” also shows up outside of criminal law. When someone believes they’ve been discriminated against at work, they can file a Charge of Discrimination with the Equal Employment Opportunity Commission. That charge is a signed statement asserting that an employer engaged in unlawful discrimination, and it triggers an EEOC investigation.14U.S. Equal Employment Opportunity Commission. Filing A Charge of Discrimination
Deadlines are tight. A complainant generally has 180 calendar days from the discriminatory act to file a charge. The window extends to 300 days if a state or local agency also enforces a law covering the same type of discrimination.15U.S. Equal Employment Opportunity Commission. Time Limits For Filing A Charge For ongoing harassment, the clock starts from the last incident. Federal employees face a shorter deadline of 45 days to contact their agency’s EEO counselor.
If the EEOC can’t resolve the matter, it issues a Notice of Right to Sue, giving the complainant 90 days to file a lawsuit in federal court.16U.S. Equal Employment Opportunity Commission. Filing a Lawsuit At that point, the complainant becomes a plaintiff, with all the costs and responsibilities of civil litigation.
What Each Role Costs
A plaintiff pays to play: filing fees, process server costs, attorney fees, discovery expenses, and potentially expert witness fees. Many personal injury plaintiffs hire lawyers on contingency, meaning the attorney takes a percentage of any recovery (typically around 33%) and the client pays nothing upfront. If the case loses, the plaintiff usually still owes litigation costs like deposition and filing fees.
A complainant in a criminal case bears no prosecution costs. The government pays to investigate, charge, and try the defendant. The complainant may lose time from work to testify, but the actual cost of prosecution falls on the state. Filing a charge with the EEOC is free, though legal costs can mount quickly if the matter escalates into a federal lawsuit after a right-to-sue letter.
Penalties for False or Frivolous Claims
Both plaintiffs and complainants face consequences for abusing the system, and they look different.
A plaintiff who files a frivolous civil lawsuit risks sanctions under Federal Rule of Civil Procedure 11. Every document filed with a court carries an implicit certification that the claims have a basis in law and fact. If a court finds otherwise, it can order the plaintiff to pay the other side’s attorney fees or impose monetary penalties paid into the court.17Legal Information Institute. Rule 11 – Signing Pleadings, Motions, and Other Papers; Representations to the Court; Sanctions Lawyers who repeatedly file groundless cases risk professional discipline on top of financial sanctions.
A complainant who knowingly files a false report with law enforcement faces criminal charges. At the federal level, making false statements to a government agency carries a penalty of up to five years in prison.18Office of the Law Revision Counsel. 18 U.S. Code 1001 – Statements or Entries Generally State penalties for filing false police reports vary and can include jail time and significant fines. The bar is higher than simply being wrong: the complainant must have knowingly provided false information. A good-faith report that doesn’t lead to charges won’t result in prosecution of the complainant.
When One Person Fills Both Roles
The labels aren’t always as clean in practice as they are in textbooks. A person who files an EEOC charge starts as a complainant and becomes a plaintiff if the matter moves to court after a right-to-sue letter. Some state court systems use “complainant” to describe anyone who initiates certain civil proceedings, though “plaintiff” remains the dominant term in civil litigation nationwide. In a case involving both criminal prosecution and a related civil lawsuit, such as a car accident where the driver faces criminal charges and the victim also sues for damages, the same person can be a complainant in the criminal case and a plaintiff in the civil one at the same time.
The labels matter less than the mechanics underneath them: who controls the case, who pays the costs, and what remedies are available. A plaintiff pursues money damages or a court order. A complainant triggers a government investigation or prosecution and waits for the system to respond. Knowing which role you’re in tells you what power you actually have.