Affidavit
A written statement of facts, sworn or affirmed under penalty of perjury before a notary or court officer — admissible as evidence in legal proceedings.
An affidavit is a formal written statement that the author (affiant) swears is true under penalty of perjury, signed before a notary public or other authorized officer. Unlike testimony given in person, an affidavit allows a witness who cannot appear (due to distance, illness, or scheduling) to provide their account for court consideration. Affidavits are used in support of motions, to establish undisputed facts, and in many administrative proceedings.
Key requirements: the affidavit must be made by someone with personal knowledge of the facts stated; it must identify the affiant; it must contain a jurat (the sworn statement language) and the affiant's signature; and it must be notarized. Statements made in affidavits are made under the same oath as live testimony — lying in an affidavit is perjury, a felony in most jurisdictions.
Common uses include: affidavits of service (confirming legal papers were properly delivered), affidavits of heirship (in probate proceedings), financial affidavits in family law (disclosing assets and income), and factual affidavits supporting or opposing summary judgment motions.
Real-World Example
The elderly witness who lived out of state and could not travel for trial submitted a notarized affidavit describing what she saw; the judge admitted it in support of the plaintiff's motion for summary judgment.