Mass. Gen. Laws ch. 51 § 44
A person seeking to register shall complete an affidavit of voter registration form as prescribed in section thirty-six, and shall sign the affidavit under the penalty of perjury. A person registering as a voter may, at the same time, establish his enrollment in a political party or political designation, as provided in section thirty-eight of chapter fifty-three, by indicating his desire to be so enrolled on the affidavit of voter registration. The affidavit of any person who provides the registrars with a copy of a court order granting protection, or evidence of residence in a protective shelter, or an affidavit signed by a chief of police or his designee that said person is entitled to have certain information withheld from the public under section 24C of chapter 265, or a program participant in the address confidentiality program established under section 2 of chapter 9A shall not be a public record.
Mass. Gen. Laws ch. 51, § 44