Apportionment of local assessment is the legislative act of determining the mode of distributing the burden of an assessment for a local improvement, designating the property out of which the tax is to be made, and establishing some certain standard of assessments. When not constitutionally restricted, the legislature may prescribe any method of apportionment which it deems equitable, unless it is palpably arbitrary and constitutes a plain abuse.
The following is an example of a state statute (New York) on apportionment of local assessment:
NY CLS Vill § 14-1416. The expense of constructing a sewerage system should be apportioned upon the lands within such area in proportion as nearly as may be to the benefit which each lot or parcel will derive therefrom, and the ratio of such benefit should be established. After a hearing, the board may modify and correct the same, or exclude land from the area of local assessment.