Sworn declaration

A sworn declaration (also called a sworn statement or a statement under penalty of perjury) is a document that recites facts pertinent to a legal proceeding. It is very similar to an affidavit, but unlike an affidavit, it is not witnessed and sealed by an official such as a notary public. Instead, the person making the declaration signs a separate endorsement paragraph at the end of the document, stating that the declaration is made under penalty of perjury.

In legal proceedings, generally, facts that rely upon an individual's memory or knowledge are most reliably proven by having the person give testimony in court: he appears in person before a judge, at a time and place known to other interested persons, swears that his testimony will be true, states his testimony so that all can hear it, and can be cross-examined by opposing parties. Generally, the written record of his testimony is taken down in written form by an official of the court, the court reporter.

Such a procedure, although maximizing fairness and the likelihood of obtaining the truth, is expensive, troublesome, and time-consuming. Therefore, in many instances, especially in preliminary or uncontested proceedings, a court will allow testimonial evidence to be given in a document filed with the clerk of court. Traditionally, this has required an affidavit: the person must put his testimony into written form and then sign the document in front of an official, such as a notary public or clerk, swearing to the official that the contents of the document are true. The official then endorses the document and generally stamps it with an official seal. Such an affidavit has several advantages over simple signed testimony:

In recent years, however, to provide for even greater economy of time and money, courts have increasingly allowed persons to omit the step of swearing before a notary public or official. Instead, the affiant puts a separate paragraph at the end of the document, such as the following (for United States federal courts):

I declare (or certify, verify, or state) under penalty of perjury that the foregoing is true and correct. Executed on (date).

Where allowed, such an endorsement gives the document the same weight as an affidavit, per 28 U.S.C. § 1746 The document is called a sworn declaration or sworn statement instead of an affidavit, and the maker is called a "declarant" rather than an "affiant", but other than this difference in terminology, the two are treated identically by the court.

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