The proposed amendment to the Constitution amends the existing constitutional provisions which direct the divisions of the Commonwealth into 240 representative districts and 40 senatorial districts. It provides for a census of the inhabitants of each city and town in the Commonwealth in the year 1971 and in every tenth year thereafter. The census in 1971 is to be the basis for determining the representative and senatorial districts for the ten-year period beginning January 1, 1975. Each subsequent census shall be the basis for determining the districts for each ten-year period beginning the fourth January following each census, so that the census in 1981 will determine the districts as of January, 1985, etc.

The amendment provides that the house of representatives shall consist of two hundred and forty members and the senate of forty members. In its first regular session following each census, the Legislature shall divide the Commonwealth into two hundred and forty representative districts of contiguous territory and forty senatorial districts also of contiguous territory. Each representatives district shall contain, as nearly as may be, an equal number of inhabitants according to the census. A representative district shall not unite two or more counties, towns, or cities, or parts thereof, or a city and a town, or parts thereof, in one district unless the same is unavoidable. Further, no town of less than six thousand inhabitants shall be divided in forming representative districts. It is also provided that the County of Dukes and Nantucket County shall each be a representative district, not withstanding the foregoing.

The senatorial districts, each of which shall elect one Senator, shall be formed without uniting two counties or parts of two or more counties, unless the same is unavoidable.

Each representative shall be an inhabitant of the district for which he is chosen at least one year immediately preceding his election, and each senator shall be an inhabitant of the district for which he is chosen at the time of his election and shall have been an inhabitant of the Commonwealth for at least five years immediately preceding his election. Any representative or senator who ceases to be an inhabitant of the Commonwealth shall cease to represent his district.

The amendment also provides that the Legislature (1) may by law limit the time within which judicial proceedings may be instituted calling in question any such division and (2) shall prescribe by law the manner of calling and conducting elections for the choice of representatives and of ascertaining their election.

Finally, the amendment annuls the existing constitutional provisions with respect to apportionment of representative and senatorial districts although those provisions will remain in effect until January 1, 1975.