Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 59, § 31

The assessors shall in all cases require a person bringing in a list to make oath that it is true. The oath may be administered by any of the assessors or by their secretary or head clerk, or by any notary public, whose jurat shall be duly authenticated by his seal, or, in this commonwealth, by a justice of the peace. So much of this section as relates to administering the oath shall not apply to Boston.