This entry contains information applicable to United States law only. Individuals who provide evidence in legal proceedings before a tribunal. Persons who have sufficient knowledge of a fact or occurrence to testify about it and who give testimony under oath in court, concerning what they have seen, heard, or otherwise observed.
Legal proceedings, especially trials, depend on witnesses to present the factual evidence to the fact finder, which may be a judge or a jury. Witnesses who have knowledge about the facts of the case and who are legally competent are required to appear in court and testify. Typically each side has its own set of witnesses, who will provide evidence favorable to one side. However, the witness must submit to cross-examination by the other side.
Attendance
Individuals who are called as witnesses have a public obligation to attend the court or legislative tribunal to which they are summoned and to give testimony. Constitutional and statutory provisions provide that the parties to a civil lawsuit have a right to compel essential witnesses to appear. This is done through the service of legal process called a subpoena, which is issued by the court. The state is also entitled to compulsory process in any proceeding in which it has an interest, either civil or criminal. An individual accused of a crime has the right to compulsory process in order to obtain witnesses on his behalf. However, the right to compel witnesses does not ensure the actual attendance of the witnesses.
In a criminal trial, a witness whose testimony is crucial to either the defense or prosecution is called a material witness. In most states, a material witness may be required to post a bond guaranteeing her appearance. In cases where a bond cannot be issued, a material witness may be confined by the police until she testifies.
Courts have inherent power to compel the attendance of necessary witnesses but this power is also generally granted by statute. State constitutions and statutes grant legislative and administrative bodies the right to compel the attendance of a witness to provide testimony concerning the issue under investigation.
An individual who receives a subpoena is bound to obey it and appear in court. Once a witness appears in court, he may be forced to attend court until dismissed by the court or by the party who summoned him. A witness must remain after the day named in the subpoena, without being served with a new subpoena, if he is wanted. Likewise, when a party or third person is present in court, the person can be called and compelled to testify without a subpoena.
A person who fails to appear and testify subject to a subpoena can be punished for contempt. In addition, the failure to appear may result in the potential witness being liable to the individual who summoned her for any damages that result from her nonappearance. Damages that result from a postponement of the trial because of the failure of a witness to attend can also be assessed. However, when the facts can be proved without the testimony of the defaulting witness, the individual who summoned the witness has no right to recover damages from her.
A witness who is not able to appear at trial may give testimony beforehand and have it recorded on videotape. The witness is examined and cross-examined by the parties and the tape is then shown at trial.
Right to Compensation
Compensation for witnesses is governed by statute and is not designed to reward them for testifying. Its purpose is merely to pay their expenses while they are away from home or work.
A witness must be in attendance in the court to be entitled to compensation, even in cases where he is not called upon to testify or proves to be incompetent to serve as a witness. Witnesses who are subpoenaed are entitled to travel expenses. Compensation for voluntary attendance depends upon state law. Some statutes provide that a witness who attends voluntarily without being subpoenaed is entitled to a daily allowance and mileage, while other state laws provide only a daily allowance, or no compensation at all.
Competency
The general rule is that a person is competent to testify if she is able to perceive, remember, and communicate, and believes that she is morally obligated to tell the truth. Legislatures have the authority to set a standard of competency for witnesses in all cases. In the case of young children, the court must assess whether the child is competent to testify.
Expert Witnesses
An expert witness is a person who, by reason of education or specialized experience is allowed to testify at a trial not just about the facts of the case but also about the professional conclusions he draws from the facts. Medical, scientific, and technical experts are commonly used, but other types of experts can be used, depending upon the facts of the case. For example, in an employment discrimination case, an economist might serve as an expert witness, providing professional testimony about discriminatory wage patterns in the affected industry. Experts witnesses generally charge a fee for their services.
Relationship to a Party
Generally a witness is not disqualified merely because she is related to one of the parties by blood or marriage. Such a relationship only affects the credibility, not the competency, of the witness.
At common law, husbands and wives were considered to be incompetent as witnesses for or against each other in civil or criminal proceedings. This consideration was based on the legal presumption that the testifying spouse was too strongly interested in the outcome of the proceedings to testify truthfully. Most states have modified the common law rule so that either spouse can testify for or against the other in civil cases. In criminal cases, one spouse can ordinarily offer testimony in favor of the other. A spouse can voluntarily testify against the other in federal prosecutions. In addition, a spouse who is a victim of the other spouse's criminal act may testify.
Privileged Communications
As a matter of public policy, certain relationships are held to be confidential and certain communications are privileged against disclosure by a witness. A witness cannot refuse to testify about a matter disclosed in a private conversation in confidence and in reliance upon the witness's promise of secrecy unless the law recognizes it as a confidential communication. Certain communications arising between an attorney and client, a husband and wife, priest and penintent, and a physician and patient are privileged against disclosure by a witness.
An individual who refuses to either provide testimony or to answer proper questions when examined before a court is liable for contempt. A mere evasive or noncommittal answer does not, however, constitute a refusal to answer that is punishable by contempt, at least when the court does not direct the witness to be more specific in his answers. A witness cannot be penalized for refusing to answer questions when the answers would violate his privilege against self-incrimination under the Fifth Amendment to the U.S. Constitution.
Credibility
Courts and juries may accept all of a witness's testimony, reject all of it, or accept part of it. A credible witness is an individual whose statements are reasonable and believable. A witness's statements are generally accepted as true unless her testimony has been discredited. Courts are reluctant to impute perjury (lying under oath) to an apparently credible witness because a witness is, in general, presumed to speak the truth.
Anything that may shed light on the accuracy, truthfulness, and sincerity of a witness can be brought out by the parties. The fact finder must decide the amount of credit to be given the person's testimony. Either party can prove facts that tend to show the weight that should be given to testimony on either side.
A party has the right in either a civil or criminal case to introduce evidence attacking the credibility of a witness for his adversary. The term to impeach a witness means to question the individual's truthfulness by offering evidence that tends to show that the witness should not be believed. A party has the right under the Sixth Amendment to confront witnesses and to cross-examine witnesses who testify on behalf of the prosecution in a criminal case.
See: Attorney-Client Privilege; Cameras in Court; Hearsay; Husband and Wife; Marital Communications Privilege; Privileged Communication; Scientific Evidence; Shield Laws.
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