If you’re notarizing for disabled signer, the best way to determine if he or she is capable of understanding the transaction — and is a willing party to it — is to engage the signer in a conversation.
Notaries may also consult an expert, such as the signer’s physician or attorney, to help determine awareness. If such an expert indicates a signer comprehends the particulars of the notarization, you can use that recommendation in deciding whether to proceed, making sure to note the expert’s conclusions and your own observations in your journal.
The ultimate responsibility for determining awareness lies with the Notary. If the comments of a physician or attorney about a signer’s awareness are at odds with your personal observations, you are justified in declining to notarize.