What is the term for a formal process involving laying an information under oath?

The correct term for a formal process involving laying an information under oath is "Affidavit." An affidavit is a written statement confirmed by oath or affirmation, used as evidence in court. It is a legal document where the signer (the affiant) swears that the contents are true, allowing it to serve as a means of presenting factual information pertaining to a case.

Laying an information under oath is critical in legal proceedings because it ensures that the information being presented has been stated under penalty of perjury, which holds the affiant accountable for its truthfulness. This process lends credibility and legal weight to the information being provided to a court or relevant authority.

The other terms—complaint, Part 3, and indictment—while related to legal processes, do not specifically refer to the act of swearing to a written statement. A complaint generally refers to the formal allegation that initiates a legal proceeding. A Part 3 Information is more specifically associated with certain types of charges in a summary conviction process. An indictment refers to a formal charge or accusation of a serious crime, typically following a grand jury's review.