Mass. Gen. Laws ch. 276 § 100B
Any person having a record of entries of a delinquency court appearance in the commonwealth on file in the office of the commissioner of probation may, on a form furnished by the commissioner, signed under the penalties of perjury, request that the commissioner seal such file. The commissioner shall comply with such request provided (1) that any court appearance or disposition including court supervision, probation, commitment or parole, the records for which are to be sealed, terminated not less than three years prior to said request; (2) that said person has not been adjudicated delinquent or found guilty of any criminal offense within the commonwealth in the three years preceding such request, except motor vehicle offenses in which the penalty does not exceed a fine of fifty dollars nor been imprisoned under sentence or committed as a delinquent within the commonwealth within the preceding three years; and (3) said form includes a statement by the petitioner that he has not been adjudicated delinquent or found guilty of any criminal offense in any other state, United States possession or in a court of federal jurisdiction, except such motor vehicle offenses as aforesaid, and has not been imprisoned under sentence or committed as a delinquent in any state or county within the preceding three years.
When records of delinquency appearances and delinquency dispositions are sealed by the commissioner in his files, the commissioner shall notify forthwith the clerk and the probation officer of the courts in which the adjudications or dispositions have occurred, or other entries have been made, and the department of youth services of such sealing, and said clerks, probation officers, and department of youth services likewise shall seal records of the same proceedings in their files.
Such sealed records of a person shall not operate to disqualify a person in any future examination, appointment or application for public service under the government of the commonwealth or of any political subdivision thereof; nor shall such sealed records be admissible in evidence or used in any way in any court proceedings or hearings before any boards of commissioners, except in imposing sentence for subsequent offenses in delinquency or criminal proceedings.
Notwithstanding any other provision to the contrary, the commissioner shall report such sealed delinquency record to inquiring police and court agencies only as "sealed delinquency record over three years old" and to other authorized persons who may inquire as "no record". The information contained in said sealed delinquency record shall be made available to a judge or probation officer who affirms that such person, whose record has been sealed, has been adjudicated a delinquent or has pleaded guilty or has been found guilty of and is awaiting sentence for a crime committed subsequent to sealing of such record. Said information shall be used only for the purpose of consideration in imposing sentence.
Mass. Gen. Laws ch. 276, § 100B