Complaints of Gerrymandering Are Based on Faulty Math - Expert

WASHINGTON - Aug. 24, 2025 - PRLog -- In trying to demonstrated how badly different states are gerrymandered, both sides are using faulty mathematics, says one of the country's leading mathematical experts on voting.

Comparing the percentage of residents in a state who voted for party X, with the percentage of representatives from party X in a legislative body, is worse than comparing apples and oranges; it's more like comparing apples with horsepower or parsecs, says Professor John Banzhaf, the inventor of the widely-used "Banzhaf Index of Voting Power."

It's a wonderful example of "Figures Don't Lie, But Politicians Don't Figure," says Banzhaf.

Just as for many years politicians believed that a system called "weighted voting" could be used instead of redistricting (even to the point that some legislators for years had no voting power), and that the Electoral College gave voters in the less populous states more voting power (actually, it's just the opposite), Banzhaf's widely-accepted mathematical analyses proved both to be wrong.

As a result, weight voting was declared unconstitutional, and the Electoral College was about to be replaced by direct elections until a Senate filibuster stymied a widely-supported proposed constitutional amendment.

But there is no valid mathematical reason to believe that the percentage of seats in a legislative body would necessarily approximate the percentage of voters for a particular party, says the professor, who explains that the relative percentages of legislators chosen by the voters would depend upon factors such as how dispersed the voters for each party

He provides the following example.

Thus the only reason that voters from the same state almost always elect legislators from both major parties is that the voters (unlike the marbles) are not distributed randomly.
Rather, some districts (or areas of the state) - which may depend upon factors such as rural v urban v suburban, or agricultural v manufacturing, etc. - will tend to be Republican leaning, while others will tend to be Democratic leaning.

Banzhaf, like virtually all impartial experts, and representatives from both political parties (although for different reasons), all agree that many of our states are grossly and unfairly gerrymandered.

But trying to prove that Republican dominated states are more gerrymandered than Democratic ones (or vice versa), simply by comparing the popular vote to the percentage of legislators elected, is like trying to determine the better car by dividing a car's horsepower by the number of cup holders it has, says Banzhaf.

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