What this § 371 charge covers
Section 371 is the general federal conspiracy law. It sits above the many conspiracy charges written for specific crimes, and it applies when the agreement itself is the crime charged. The statute reads in full:
"If two or more persons conspire either to commit any offense against the United States, or to defraud the United States, or any agency thereof in any manner or for any purpose, and one or more of such persons do any act to effect the object of the conspiracy, each shall be fined under this title or imprisoned not more than five years, or both."
That one paragraph holds two separate charges. The first, called the offense clause, covers agreements to commit any federal crime: fraud, theft, firearms offenses, immigration offenses, and the rest. The second, called the defraud clause, covers agreements to cheat the United States or any of its agencies in any manner or for any purpose. Tax cases are a common example of the second kind. The guideline commentary for tax conspiracies cites United States v. Klein, which is why lawyers often call agreement-to-obstruct-the-IRS cases Klein conspiracies. Either way the structure is the same: an agreement, plus at least one overt act by any member of the group.
Conspiracy is part of the broader group of federal crimes, but it works differently from most of them. The agreement is the crime. The plan does not have to succeed, the money does not have to move, and the government does not have to prove you personally carried out any part of the plan. If you are reading this because agents have contacted you or someone close to you, skip to the last section first, then come back.
What the government must prove under § 371
The Ninth Circuit's model jury instructions break a general conspiracy charge into three pieces the government must prove beyond a reasonable doubt. First, "there was an agreement between two or more persons to commit at least one crime as charged in the indictment." Second, "the defendant became a member of the conspiracy knowing of at least one of its objects and intending to help accomplish it." Third, "one of the members of the conspiracy performed at least one overt act" done "for the purpose of carrying out the conspiracy."
Each piece has a trap for the unwary. The agreement does not have to be formal. The Ninth Circuit's instructions state that no written plan and no agreement on every detail is required, and that a member can join without knowing every detail or every other member. What is required is a shared plan to commit a specific crime charged in the indictment, with the jurors agreeing on which crime the group agreed to commit. Parallel conduct is not enough. People who simply met, talked, acted in similar ways, or helped one another without a shared criminal plan have not conspired.
Knowledge and intent do the heaviest work. The instructions describe conspiracy as "a kind of criminal partnership," meaning "an agreement of two or more persons to commit one or more crimes." Joining requires knowing participation with the intent to advance the plan. A person who furthers the plan by accident, without knowing a conspiracy exists, is not a member. And the instructions draw the line plainly: "a person does not become a conspirator merely by associating with one or more persons who are conspirators, nor merely by knowing that a conspiracy exists." Being near a conspiracy, being related to a conspirator, or knowing something criminal was happening is not the same as joining it.
The overt act is the third element, and it surprises many people. The Ninth Circuit's instructions state that "An overt act does not itself have to be unlawful." A lawful step counts if it was done to move the plan forward. Only one member needs to act, the government does not have to prove you personally did it, and the jurors need not agree unanimously on which act it was. But the act must be tied to the plan. Everyday conduct with no connection to the agreement proves nothing, and the defense in many cases is built on cutting that link: the act happened, but it had nothing to do with any conspiracy.
Penalties on paper under § 371
Each count under section 371 carries up to five years in prison. There is one built-in ceiling worth knowing. "If, however, the offense, the commission of which is the object of the conspiracy, is a misdemeanor only, the punishment for such conspiracy shall not exceed the maximum punishment provided for such misdemeanor." A conspiracy to commit a misdemeanor cannot be punished more harshly than the misdemeanor itself.
Fines follow the general federal fine law. An individual convicted of a felony faces a fine of "for a felony, not more than $250,000," while an organization faces "for a felony, not more than $500,000." On top of that, when the offense produced gain or caused loss, "the defendant may be fined not more than the greater of twice the gross gain or twice the gross loss." A prison term can be followed by supervised release. A five-year maximum makes the offense what the classification law calls "less than ten years but five or more years, as a Class D felony," and for a Class D felony supervised release runs "for a Class C or Class D felony, not more than three years."
Time limits are strict on paper and generous in practice. The general federal limitations law provides that "no person shall be prosecuted, tried, or punished for any offense, not capital, unless the indictment is found or the information is instituted within five years next after such offense shall have been committed." In conspiracy cases the Ninth Circuit's instructions account for this by directing that, when timing is in dispute, the jury can be required to find that an overt act happened inside the limitations period. Old agreements with recent steps can therefore still be charged, which is why the date of the last act the government alleges matters so much.
Repeat the caution because it matters. Five years, the fines, and supervised release are statutory maximums stated in the abstract. They are not predictions. There is no mandatory minimum under section 371, so the floor is set by the guidelines and the judge. The facts of a case change everything.
How the sentence is actually calculated
Section 371 has no guideline of its own for most cases. The Guidelines Manual sends the sentence through the guideline for the crime the group planned. The Statutory Index in Appendix A maps section 371 to several guidelines depending on the object: 2A1.5 for murder-related conspiracies, 2C1.1 for conspiracies to defraud through interference with government functions, 2K2.1 for conspiracies involving certain firearms offenses, 2T1.9 for tax conspiracies, and 2X1.1 as the general conspiracy rule. The court picks the one that fits the conduct charged, and the choice changes the math completely.
The general rule, guideline 2X1.1, starts the sentence at the level for the planned crime, then asks how far the plan got. The Manual directs: "If the offense involved a conspiracy, attempt, or solicitation, refer to §2X1.1 (Attempt, Solicitation, or Conspiracy) as well as the guideline referenced in the Statutory Index for the substantive offense." From that starting point, the rule gives a break for plans caught early: "If a conspiracy, decrease by 3 levels," unless the group finished everything it believed necessary or was about to finish but for being caught. The commentary explains when the break does not apply: "In such cases, no reduction of the offense level is warranted" where the planned crime was completed or stopped on the verge of completion. And only adjustments the group actually intended or actually brought about count: "Speculative specific offense characteristics will not be applied." A conspiracy to rob a bank sentences like a bank robbery for its base level, but imagined injuries and unobtained money do not pile on.
Two more mechanics matter. When one count charges a conspiracy with more than one criminal object, the Manual treats it as a separate conspiracy count for each object the defendant joined, which affects how counts group and add up. And the guideline range can never exceed what the statute allows: "The sentence that shall be imposed is limited, however, to the maximum authorized by the statute under which the defendant is convicted." For most section 371 cases that means the five-year ceiling caps the sentence even when the planned crime would otherwise produce a higher range. Our federal sentencing page walks through how that hearing works.
Tax conspiracies follow their own rule, guideline 2T1.9. The base level is the greater of the tax offense level or level 10: the rule says to "Apply the greater," taking the "Offense level determined from §2T1.1 or §2T1.4, as appropriate" or 10, whichever is higher. Two enhancements stack on top. Planned or threatened violence to obstruct tax collection adds 4 levels. Conduct meant to encourage people beyond the conspirators to break the tax laws adds 2 levels, which is aimed at protest groups and marketed tax shelters. But the rule has a stated limit: "It does not apply to taxpayers, such as a husband and wife, who merely evade taxes jointly or file a fraudulent return." A couple filing a false joint return is a tax case, not a tax conspiracy case under this guideline.
This charge versus its closest neighbours
Conspiracy law has several nearby statutes, and the name of the one charged decides what the government must prove. The most important neighbour is drug conspiracy under 21 U.S.C. 846, covered on our drug conspiracy page. Its text is one sentence: "Any person who attempts or conspires to commit any offense defined in this subchapter shall be subject to the same penalties as those prescribed for the offense, the commission of which was the object of the attempt or conspiracy." Two differences follow. First, the text lists no overt act, and the Ninth Circuit's commentary confirms that no overt-act proof is needed for drug conspiracies. Second, the penalty follows the planned drug crime, including any mandatory minimum, rather than the five-year ceiling of section 371. A drug case charged under section 371 looks very different at sentencing from the same conduct charged under section 846, so counsel checks the statute number on the indictment first.
Money laundering conspiracy works the same way on the overt-act point. The Ninth Circuit's commentary notes that no overt-act proof is needed for conspiracy to commit money laundering either. Our money laundering page covers that companion charge, which is often added when the government says the group moved its proceeds through accounts to hide them.
Fraud conspiracies deserve their own mention because they are the most common section 371 cases. When the alleged agreement was to commit wire fraud, bank fraud, or health care fraud, the conspiracy count usually travels with substantive fraud counts, and each count needs its own proof. Our fraud conspiracy page covers that setting. And where the government alleges an ongoing criminal enterprise rather than a single agreement, it may charge RICO conspiracy instead, a different statute with different proof. Our RICO page explains that charge.
Defenses and issues that actually arise
Every case turns on its facts, but section 371 defenses cluster in a few places. First, the agreement itself. Was there a shared plan to commit a specific federal crime, or only parallel conduct, talk, and association? The government often proves agreement through texts, meetings, money movement, and cooperating witnesses. The defense tests whether those facts show a real meeting of the minds or something else: a buyer-seller relationship, independent actors chasing the same opportunity, or conduct by others the accused never joined. In drug-adjacent cases the Ninth Circuit gives this argument a name: "A buyer-seller relationship between a defendant and another person, standing alone, cannot support a conviction for conspiracy." Repeated sales alone, even in quantity, are not an agreement without more.
Second, which prong. Offense-clause and defraud-clause cases need different proof, and the government sometimes charges the easier one and sometimes overreaches. A plan to cheat an agency through deceit fits the defraud clause. Conduct with no deceit behind it may not, and a plan aimed at private victims rather than the government belongs under a different statute.
Third, the overt act. Was there any act at all, was it done to carry the plan forward, and did it happen inside the limitations period? Because a lawful act can qualify, this fight is usually about purpose and timing, not about whether the act was itself a crime.
Fourth, withdrawal. A member who genuinely quits can cut off liability, but the standard is demanding. The Ninth Circuit's instruction states: "One may withdraw by doing acts which are inconsistent with the purpose of the conspiracy and by making reasonable efforts to tell the co-conspirators about those acts." Quitting quietly, getting arrested, or simply becoming inactive does not qualify. And the burden sits with the accused: "the burden is on the defendant to prove by a preponderance of the evidence" that withdrawal happened before the overt act the jury agreed on. Done in time, withdrawal is powerful. The instruction's commentary notes that "A defendant who withdraws outside the relevant statute-of-limitations period has a complete defense to prosecution."
Fifth, the sentence math. Which guideline did the court pick from the Appendix A list, does the 3-level reduction for an incomplete plan apply, which adjustments were truly intended or actually occurred, and does the five-year ceiling cap the range? Each question is open to proof, and each level on the table is worth fighting.
If you are under investigation
Act early and say little. Do not meet agents without counsel, and do not assume that talking your way out is possible when membership turns on what you knew and intended. Everything you say about who agreed to what can become the agreement evidence. Do not write out your side of the story in email or text. Do not delete, shred, or backdate anything, and do not ask anyone else to lie or stay silent. Obstruction and witness-tampering charges are easier to prove than the underlying conspiracy, and they raise every sentence.
Get counsel a complete picture at the first meeting: every contact with agents, any subpoena, search, or target letter, and the names of everyone involved. In conspiracy cases the difference between a witness, an unindicted associate, and a defendant is often decided in the first weeks, before any indictment exists.