Alabama Voting Rights Ruling Based Upon Dubious Math

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Alabama Voting Rights Ruling Based Upon Dubious Math; But Math, and Possibly AI, May Be Able To Help

Alabama Voting Rights Ruling

WASHINGTON D.C. (June 8,2023) – Today’s Supreme Court voting rights decision appears to rest on the dubious mathematical assumption that the “minority group won fewer seats in the legislature than its share of the population,” but more sophisticated mathematics, and possibly artificial intelligence [AI] programs, might help achieve truly impartial and less unfair voting maps, says public interest law professor John Banzhaf.

The professor is the creator of the “Banzhaf Index of Voting Power” (or “Banzhaf Power Index”), a widely adopted technique which uses mathematics and complex computer calculations to determine to what extend voters in different districts have unequal voting power, and which has been adopted as a constitutionally required standard by the highest court in New York.

Although it is widely believed that, if a state has X% of voters with a distinct voting preference (e.g., Black voters or Republican voters), a fair election with impartially drawn districts will result in roughly X% of such legislators being elected.

For example, if the state of Columbia has 100 voting districts and 55% of the voting population are Republicans who almost always vote for Republican candidates, Columbia’s House of Representatives will be made up of approximately 55% Republicans and 45% Democrats.

But as virtually any mathematician can assure you, if voters from the two parties are uniformly distributed among the 100 voting districts, the result will be that each and every one of the 100 districts will have 55% Republican voters, and the percentage of Democrats elected to the House will be 100%.

In reality – since even in the reddest or bluest states there are some members of the other party elected to the House – the distribution of legislators who are Republican (or in case such as Allen v. Milligan who are Black) will be determined by a variety of factors such as the non-uniform distribution of the minority among the general population.

Adoption Of Gingles

Fortunately the majority opinion recognizes this simple mathematical truth, and has therefore adopted a complex and largely subjective test (“Gingles”) which includes factors such as the whether the “minority group must be sufficiently large and [geographically] compact to constitute a majority in a reasonably configured district.”

Fortunately, there are several different mathematical techniques which can be used to map out districts which are not only roughly equal in population, but also reasonably configured and not gerrymandered, says Banzhaf, and such computer programs have been used to generate maps which are often seen as less unfair than those concocted by legislators.

But now, with recent exponential advances in using computers to solve a wide variety of problems – including, most recently, very “intelligent” AI programs – it may soon be possible to turn the entire task of redrawing voting maps to computers, with the resulting maps being at least the starting point (“initial condition”) for voting maps presented to the legislature for adoption.

In the alternative, under today’s decision, those representing Black votes and arguing illegal diminution of their voting power under §2 might be able to use such computer generated maps to help prove their case by providing an alternative map which is arguably impartial and therefore less unfair, suggests Banzhaf.