Say someone concocts a sworn declaration regarding income, and expects to use this as a means of either proving income to a seller/service, etc. Can the sworn declaration be notarized to make it valid?
I mean, of course, more valid as in proving that the statement was signed by the person presenting it.
The point of notarizing a document is to provide official evidence that the person in question did sign the document: you establish your identity, and sign in the presence of a notary who then affixes their seal and signature saying "I saw him sign this". Whether or not the statements in the document are true is a separate matter: all that notarizing does is resolve the question whether it was X who signed the statement.
When testifying or providing a written factual claim in an official government matter, you may be required to, in some form, "swear" to the truth of a claim – you take an oath, required or authorized by law, and you have been apprised of the fact that lying on the statement is punishable. Only certain people can, by law, administer such an oath, and if the oath is in a written statement, it has to be an official form with appropriate perjury notifications. There may be a particular requirement to provide a "sworn statement", e.g. Minnesota has a family violence waiver law that requires such a statement. A "sworn statement" in that sense and as distinguished from an affidavit is not notarized. One may still submit an affidavit (not a "sworn statement"), if allowed, in an official matter: here are the Washington state rules for subscribing to an unsworn statement. State law may require an affidavit to be notarized (an example from Colorado). So: if by "sworn statement" you mean "affidavit", then notarization may be required by local law.
Yes, a declaration can be notarized. Anything can be notarized. But the effect of a declaration is not the same as an affidavit. I assume that is what you want. If it's for the purpose of court, a notarized "Affidavit of Truth" is the way to go.
The reason for using a sworn and notarized Affidavit is because, unrebutted, it stands as truth, prima facie ('on it's face').
Here are some judicial quotes from court cases.
"Indeed, no more than affidavits is necessary to make the prima facie case.” [United States v. Kis, 658 F.2d 526, 536 (7th Cir. 1981); Cert. Denied, 50 U.S. L. W. 2169; S. Ct. March 22, 1982]"
"Allegations in affidavit in support of motion must be considered as true in absence of counter-affidavit.” [Group v Finletter, 108 F. Supp. 327 Federal case of Group v Finletter, 108 F. Supp. 327]"
"An affidavit uncontested unrebutted unanswered Morris vs. NCR, 44 SW2d 433 Morris v National Cash Register, 44 SW2d 433: [point #4] “An Affidavit if not contested in a timely manner is considered undisputed facts as a matter of law."
A sworn declaration only proves that the declarer believed what they have sworn is true: this doesn't make it true - it only means someone believes that it is true. If you want evidence to prove income you need more than this: payslips, tax returns and bank statements are evidence, a declaration is just a piece of paper.
