Mass. Gen. Laws ch. 148 § 3
The marshal shall investigate or cause to be investigated the circumstances of all fires or explosions of suspicious origin of which he has notice, and may investigate or cause to be investigated the circumstances of any fire or explosion occurring anywhere within the commonwealth. For such purposes the marshal, or his designee, may summon and examine on oath, administered by the marshal or such person so designated, any person supposed to know or have means of knowing any material facts touching the subject of investigation. Such witnesses may be kept apart and examined separately, and such examination shall be reduced to writing, and false testimony therein shall be perjury. Any justice of a district court or of the superior court, upon application of the marshal, or person so designated, may compel the attendance of such witnesses and the giving of such testimony in the same manner and to the same extent as before said court. If, upon such investigation, the marshal, or person so designated, believes that the evidence is sufficient to charge any person with crime, he shall make a complaint therefor, and shall furnish the proper officers with the evidence and names of witnesses obtained by him. The marshal shall, when required, report to the commissioner of insurance his proceedings and the progress of prosecutions instituted hereunder.
Mass. Gen. Laws ch. 148, § 3