In the case, the court believed that the license was probably actually issued by the DMV, as opposed to a cut and paste job.  Not sure how it was obtained by the con artist, or why there was an alleged discrepancy with the birthdate/ expiration date. 

The court hinted that a reasonably diligent notary might be expected to spot an altered license, but I would suppose that would depend on how good the fake was. Merely looking at a document that is put forth by the signor as a license is not going to be enough of an excuse for a notary, if it is an obvious fake-- for example, in a California criminal case (People v. Wilson, 2013 WL 1271640), a notary was convicted of crimes involving a fraudulent notarization where she tried to create cover for herself by having the signors present a purported drivers' license.  Her excuse was damaged by the fact that another notary who was presented with the same license testified that it "looked typewritten" and didn't even look like a California license.