Massachusetts General Laws Part III. Courts, Judicial Officers and Proceedings in Civil Cases (Ch. 211-262) Ch. 222, § 19

A notary public shall perform a notarial act for any person requesting such act who tenders the fee provided for in section 41 of chapter 262 or any other general or special law or executive order, unless:

(i) the notary public knows or has reason to believe that the notarial act or the associated transaction is unlawful;

(ii) the principal has a demeanor that causes the notary public to have a compelling doubt about whether the principal knows the consequences of the transaction or document requiring the notarial act;

(iii) the act is prohibited by this chapter or any other applicable law; or

(iv) the number of notarial acts requested practicably precludes completion of all acts at once, in which case, the notary public shall arrange for later completion of the remaining acts.