When a person executes an affidavit, and the court relies on it, then intentionally lying on the affidavit, in a material manner, can constitute perjury. I stress "intentionally" and "material," and it must be a false statement of fact, not merely opinion. For example, if your wife said that someone is a "bad father," but he was really a good dad, that would not be perjury because it is merely opinion. On the other hand, if your wife said that she saw you beat your child with a baseball bad, and she knew this was a lie, this would probably be perjury.
Marc A. Pederson
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