Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 60, § 87

A city or town may, by ordinance or by-law, respectively, direct whether its collector shall exercise the power of sale or the power of taking to enforce the lien for taxes; and in default of such ordinance or by-law the collector may exercise either power at his discretion; but the passage of any such ordinance or by-law shall not render invalid any proceedings then pending.