DO: Check your state's laws regarding proof of execution by subscribing witness before proceeding
As a last resort, a proof of execution by subscribing witness is sometimes used when the document's principal signer cannot appear before a Notary. In that event, a subscribing witness appears before the Notary and attests that the absent principal willingly signed the document. However, not all states allow proofs of execution. Others limit their use. In California, proofs may not be used for signatures on mortgages, security agreements, deeds of trust or grant deeds. In addition, some states allow proofs only if the subscribing witness watches the principal sign. But in other states, this is not necessary, provided that the principal acknowledges having signed the document to the subscribing witness.
DO: Have a subscribing witness sign the document
The subscribing witness is so named because this person also must sign, or "subscribe," on the document as a witness in addition to the principal's signature.
DON'T: Use a proof of execution as a casual convenience for the signer
Proofs of execution should only be performed as a last resort because they contain high potential for misuse. A proof shouldn't be used simply because a signer has a prior appointment and can't appear in person before a Notary. It would be a different matter, however, if the principal were comatose in a hospital or on a month-long research assignment to Antarctica. Remember, proofs of execution should not be used merely to avoid inconveniencing a friend, client or employer.
DO: Positively identify the subscribing witness
Most states require a subscribing witness to be personally known by the Notary. One state (North Carolina) expressly allows Notaries to rely on ID to identify subscribing witnesses. California requires a subscribing witness to either be personally known by the Notary, or to be vouched for by another credible witness who is personally known to the Notary and presents a state-approved ID.