Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 58, § 10

In determining the equalized valuations required by section nine, the commissioner shall make and issue such comprehensive assessment ratio studies of the average level of assessment, the degrees of assessment, uniformity, and over-all compliance with assessment and classification requirements for each major class of property in each city and town of the commonwealth as he shall deem appropriate to indicate the degree of compliance with the law and rules and regulations for the assessment and classification of property in each city and town.

For the purposes of this section, the commissioner shall collect and tabulate information relative to all sales of real estate and shall also cause appraisals to be made of properties of various classes in each city and town sufficient in number and so selected, by random sampling or otherwise, as to (a) confirm the assessment ratio derived from selling prices, (b) assist in determining assessment ratio wherever the number of sales is insufficient to represent all properties of any specific class in a city or town, (c) provide a substitute for selling prices of properties of a unique character or which are sold at infrequent intervals, and (d) establish an assessment ratio for personal property assessed in each city or town.

The commissioner may require from state, city and town officers and from individual property owners such returns and statements relative to the amount and value of taxable property and the income derived therefrom in the several cities and towns as he deems necessary. If a city or town fails to submit such information in its possession or which it can reasonably be expected to obtain as the commissioner requests in writing for use in determining the equalized valuations required by section nine and such failure continues for thirty days after such written request, such city or town shall not have a right to submit testimony to the commissioner as provided under section ten A and the decision of the commissioner with respect to such city or town shall be final.