Concept
The Constitutional Guarantee
Privilege against self-incrimination
The Constitutional Guarantee
The Self-Incrimination Clause turns on a single operative word, because no person "shall be compelled in any criminal case to be a witness against himself."1 Compulsion is what separates a constitutional violation from the countless occasions on which people incriminate themselves freely, which is why the guarantee is sometimes described more accurately as a privilege against compelled self-incrimination.2 The Fifth Amendment leaves a person free to make damaging statements and stops only the government from forcing them out. Every later rule in this reading, from silence at trial to silence after police warnings, builds on that line between speech the person chose and speech the government extracted.
The Court has stated what the clause secures in a form that contains two separate promises. When it applied the guarantee to the states, it described the privilege as "the right of a person to remain silent unless he chooses to speak in the unfettered exercise of his own will, and to suffer no penalty . . . for such silence."3 The first promise is the right to silence itself, which leaves the decision to speak with the person and not with the government. The second promise is freedom from punishment for choosing silence. That second half does most of the work in the sections that follow, because an official who wants a statement seldom needs to order it and can instead make silence expensive. A person who may stay quiet only by accepting a penalty has the right on paper, yet the choice is no longer unfettered. The Court said exactly this about prosecutorial comment on a defendant's silence: it "cuts down on the privilege by making its assertion costly."4
The penalty that amounts to compulsion need not be physical. A state employee who is told to answer investigators' questions or lose the job has been compelled, and in Garrity v. New Jersey the Court held that answers given under that threat cannot be used in a later criminal prosecution of the employee.5 How much hardship counts as compulsion is a question of degree. In McKune v. Lile the Court upheld a prison treatment program that tied privileges to disclosure of past crimes, because losing privileges and moving to a maximum-security unit were not onerous enough to compel the inmate to incriminate himself.6
The clause speaks of a "criminal case," yet the guarantee is not confined to the courtroom where a defendant sits. The harm it guards against is being made a witness against oneself, so what matters is whether an answer could later be used to prosecute, and the kind of proceeding that demands the answer is secondary. The Court has said the privilege can be asserted in any proceeding, civil or criminal, administrative or judicial, investigatory or adjudicatory, and that it covers disclosures the witness reasonably believes could be used in a prosecution or could lead to other evidence that might be.7 The reasoning behind that reach is historical. When the Court first extended the clause beyond the accused at his own trial, it observed that the compulsion of testimony and its use in a criminal case need not happen at the same moment.8 In Miranda v. Arizona the defendant was arrested at home, taken to a police station, and questioned for two hours until he signed a confession, with no court involved at any point, and the Court held that the privilege protects people in all settings in which their freedom of action is curtailed from being compelled to incriminate themselves.9 The warnings and waiver rules that grew from that holding belong to a separate reading.
Two applications show how the "any proceeding" principle sorts cases. A witness in a civil suit over a car crash who is asked whether she was robbing a store on the day of the accident may decline to answer even though she has never been charged, because the answer might be used in a later prosecution for the robbery. A grand jury witness asked about drug use decades earlier, after the limitations period for that offense has long run, has no real fear of prosecution and therefore nothing to protect.10 The trigger is accordingly twofold: government compulsion, and a possibility of criminal prosecution that is more than fanciful.11 The privilege is also personal, so only the person who is at risk may claim it, and no one may assert it on another's behalf.12
The word "witness" supplies a further limit. Read in light of the common law, it confines the privilege to evidence of the kind a witness provides, meaning testimonial or communicative evidence that reveals the contents of the mind.13 In Schmerber v. California the police had blood drawn from a driver over his objection. The Court agreed that this was compulsion but held that the blood and its chemical analysis were not testimony, so the privilege was not violated.14 The line is contested at its edges. When the accused in United States v. Wade was made to speak the robber's words at a lineup, the Court relied on Schmerber to reject his privilege claim, and Justice Black, who had dissented in Schmerber itself, would have treated both the blood and the voice as proof the government forced a person to supply against himself.15 Justice Fortas, joined by the Chief Justice and Justice Douglas, objected on narrower ground: compelled speech is a volitional act within the historical perimeter of the privilege.16
The Justices have also divided over what kind of guarantee the clause is. In Chavez v. Martinez, Justice Thomas, writing for four Justices, read the text to mean that the clause itself is violated only when a compelled statement is used in a criminal case, with protection for witnesses outside the trial resting on judicially created safeguards. Justice Kennedy, writing for three, read it as a substantive constraint on government conduct that protects a person from being forced to give answers in any context where they might lead to criminal liability.17 For most purposes the disagreement changes little, since a witness may refuse to answer incriminating questions under either reading.
The values behind the guarantee explain both its halves, and the history comes first. In the fifteenth through seventeenth centuries the Star Chamber and the High Commission forced people accused of religious or political crimes to testify under oath, subjected them to rigorous questioning, and often tortured them. The English common-law privilege arose in opposition to the oath used in those courts' investigations, and the Fifth Amendment carried that privilege into the Constitution.18 The practical predicament compelled testimony creates is what the Court has called the cruel trilemma of self-accusation, perjury, or contempt: a person ordered to answer can incriminate himself, lie under oath, or refuse and be punished.19 The right to refuse removes the trilemma, but only if refusal carries no punishment, which is why the second promise cannot be separated from the first.
Three further reasons shape how far the rule extends. The first is structural and runs on incentive: an investigator who may extract proof from the suspect has less reason to gather proof elsewhere, so the guarantee pushes the state toward the independent investigation that the accusatorial system assumes, requiring the government to produce the evidence against a person by its own labors and not by compelling it from the person's own mouth.20 The second concerns reliability. Self-accusation is an unreliable instrument that tends to implicate the innocent but weak, and the Court has recognized the privilege as a protection to the innocent as well as the guilty.21 Yet reliability is not the whole of it, since a coerced confession is excluded even if it is true.22 The third is respect for the dignity of the individual and for a private enclave where a person may lead a private life.23 Privileges for confidences in the attorney-client or spousal relationship protect relationships society wants to foster, whereas this privilege limits the government's invasion of the individual's security, and that is why it operates only against government compulsion.24
Those reasons also show why silence cannot be turned into proof of guilt. If a jury may infer guilt from invocation, using the privilege is penalized in practical terms, and the privilege may then produce the very harm it exists to prevent.25 A jury told that an innocent person would have spoken has been invited to punish the choice the clause secures, and the trilemma returns in softer form as a choice between speaking and being presumed guilty. The sections that follow take up each way the government has tried to attach that cost, beginning with how the privilege came to bind the states.