Perjury, the crime of lying under oath, is a serious offense because it can derail the basic goal of the justice system—discovering the truth. Even the famous and the powerful have faced the consequences of perjury, which include prosecution, prison, and impeachment.
"I swear to tell the truth, the whole truth, and nothing but the truth." It's an oath so familiar that its significance can be overlooked. But, when sworn in a court or other official proceeding, it makes everything said afterward either the truth or perjury.
Historically, perjury was defined as lying while testifying in court. The law now defines the crime to cover not just trials but also many other proceedings, including grand juries, family law court, bail hearings, Congressional committee hearings, and depositions in civil lawsuits. Sworn statements made to governmental agencies such as the Social Security Administration or in financial affidavits (such as loan applications) are also covered.
It's also a criminal offense to cause another to commit perjury, called suborning perjury.
To convict on perjury charges, a prosecutor must prove a person knowingly made a false statement of material fact under oath. All parts of this definition are important, so let's take a closer look at each and some examples of perjury.
Perjury can take the form of oral or written statements made under oath or affirmation. For instance, a witness giving testimony at trial makes an oral statement under oath. Statements made outside of court can also be subject to perjury charges. For instance, a person might provide testimony under oath at a deposition or Congressional hearing. Someone who intentionally lies about their assets on a written loan application may also sign under penalty of perjury.
The witness must know that the testimony is false. False testimony that results from confusion, memory lapse, or mistake is not perjury. Conflicts in testimony may be perjury if one of the conflicting statements is necessarily false. (In such a case, prosecutors can prove perjury without proving which one is false).
Let's say one witness testifies the get-away car was black but another witness says blue. Neither has committed perjury if their memories are simply unclear. But if one of those witnesses purposely states the wrong color in hopes to mislead the jury, that witness commits perjury.
The false statement must be capable of influencing the proceeding or issue in question—that is, it must have a relationship to whatever issue is being decided. A lie, even under oath, about a subject that is not material to the proceeding is not perjury. For example, falsely bragging that "I never update my Instagram page at work," while testifying in a case having nothing to do with social networking at work, would not be a likely candidate for a perjury charge.
A person convicted of perjury under federal law may face up to five years in prison and fines. (18 U.S.C. § 1621.) The punishment for perjury under state law varies from state to state but is typically a felony. Felonies carry a possible prison sentence of at least one year, plus fines and probation.
If a witness commits perjury in an attempt to hide or assist another in a crime, the prosecutor might skip the perjury charges and file charges for conspiracy or aiding and abetting a crime. This situation might occur if these charges carry a greater penalty than perjury.
In some cases, the prosecutor will call a defendant to testify solely because the prosecutor knows that the defendant will likely lie under oath, committing perjury. The prosecutor doesn't need the testimony for any other purpose. In these cases, a defendant might claim prosecutorial misconduct and the prosecutor will deny it.
Whether or not a prosecutor has actually set this "perjury trap," it's a hard defense to prove. Just because the prosecutor hopes the witness will lie, doesn't make the witness do so. As long as the questions asked of the witness are related to the issue under investigation or raised in a lawsuit, the prosecutor is not setting a trap, even if the prosecutor harbors a hope that the witness will lie. If the prosecutor asks irrelevant questions, perjury charges won't likely stick anyway because they're not material statements.
Perjury can be a complex crime. As with all serious legal problems, be sure to consult a criminal defense lawyer if you have questions about perjury or find yourself the subject of a criminal investigation or charges. An experienced lawyer can evaluate the strength of the case against you, the viability of any defenses, and the chances for a favorable outcome either through plea negotiations or at trial.