28 CFR § 51.54 - Discriminatory purpose and effect.
(a) Discriminatory purpose. A change affecting voting is considered to have a discriminatory purpose under section 5 if it is enacted or sought to be administered with any purpose of denying or abridging the right to vote on account of race, color, or membership in a language minority group. The term “purpose” in section 5 includes any discriminatory purpose. 42 U.S.C. 1973c. The Attorney General's evaluation of discriminatory purpose under section 5 is guided by the analysis in Village of Arlington Heights v. Metropolitan Housing Development Corp., 429 U.S. 252 (1977).
(b) Discriminatory effect. A change affecting voting is considered to have a discriminatory effect under section 5 if it will lead to a retrogression in the position of members of a racial or language minority group (i.e., will make members of such a group worse off than they had been before the change) with respect to their effective exercise of the electoral franchise. Beer v. United States, 425 U.S. 130, 140-42 (1976).
(1) In determining whether a submitted change is retrogressive the Attorney General will normally compare the submitted change to the voting standard, practice, or procedure in force or effect at the time of the submission. If the existing standard, practice, or procedure upon submission was not in effect on the jurisdiction's applicable date for coverage (specified in the Appendix) and is not otherwise legally enforceable under section 5, it cannot serve as a benchmark, and, except as provided in paragraph (c)(4) of this section, the comparison shall be with the last legally enforceable standard, practice, or procedure used by the jurisdiction.
(3) The implementation and use of an unprecleared voting change subject to section 5 review does not operate to make that unprecleared change a benchmark for any subsequent change submitted by the jurisdiction.
(4) Where at the time of submission of a change for section 5 review there exists no other lawful standard, practice, or procedure for use as a benchmark (e.g., where a newly incorporated college district selects a method of election) the Attorney General's determination will necessarily center on whether the submitted change was designed or adopted for the purpose of discriminating against members of racial or language minority groups.
(d) Protection of the ability to elect. Any change affecting voting that has the purpose of or will have the effect of diminishing the ability of any citizens of the United States on account of race, color, or membership in a language minority group to elect their preferred candidates of choice denies or abridges the right to vote within the meaning of section 5. 42 U.S.C. 1973c.