Mass. Gen. Laws ch. 34B § 1
The government of each of the following counties, in this chapter called an "abolished county" is hereby abolished as of the following date, in this chapter called the "transfer date", or on such earlier date 30 days after the commissioner of revenue certifies in writing that the county has failed to make a required payment on an outstanding bond or note: (a) Middlesexcounty, as of July 11, 1997; (b) Hampden and Worcester counties, as of July 1, 1998; (c) Hampshire county, as of January 1, 1999; provided, however, that all functions, duties and responsibilities for the operation and management of the jail, house of correction and registry of deeds of Hampshire county and all duties and responsibilities for operation and management of property occupied primarily by the sheriff, registry of deeds and the trial courts in Hampshire county are hereby transferred to the commonwealth, effective September 1, 1998, subject to the provisions of this chapter; (d) Essex county as of July 1, 1999; and (e) Berkshire county on July 1, 2000, but all functions, duties and responsibilities for the operation and management of the registries of deeds of Suffolk and Berkshire counties and all duties and responsibilities for the operation and management of property occupied primarily by the registries of deeds in Berkshire and Suffolk counties are hereby transferred to the commonwealth, effective on July 1, 1999, subject to the provisions of this chapter.
Mass. Gen. Laws ch. 34B, § 1