The District Court Ruling in Favor of Montana
In a two-to-one majority, the district court ruled in favor of Montana, citing several reasons, with Judges Lovell and Batin (both from Montana), in majority.
The first ruling was in determination of how best to apply the “one person, one vote” principle set forth by the precedent in this matter, namely Wesberry v. Sanders (1964) [64]. Secondly, while that case did not set forth a test for this principle, Karcher v. Daggett (1983) [83] ruled that "districts be apportioned to achieve population equality as nearly as practicable”. Thus Lovell and Batin held that absolute differences, or the difference between the number of Representatives per person among states, in district size be used as the only proper standard for testing district equality, as argued by Montana [92b].
Relative difference (proportions or percentages) were ruled as improper, as this assigns numbers to groups, taking away individual voting power, not accounting for actual voting outcome caused by disparities in population. Moreover, calculating shares of a representative was seen as incorrect as it violated Congress’ rule that one house be chosen by population. Despite this evidence, not all Supreme Court judges were convinced, which perhaps foreshadows the case being overturned later [92b]. While the above is meant to demonstrate that absolute difference should be the standard measure of equality, no test was recommended in the decision; rather, many choices were offered with no clear recommendation. Choices were stated as variance between actual and district size, range, deviation from ideal district size, and a normal distribution around the mean district size. Variance was mentioned again by the majority as a traditional method of proper representation, as well as absolute difference.
Another oddity in the decision is that, mathematically, Huntington-Hill apportionment agrees with a lot of the majority opinions. However, this method is in favor of the Defense’s argument, so it is unclear why this is not explicitly stated or acknowledged by the Court. They indirectly address this when they state that the method’s true nature is to minimize relative difference, a concept that was previously ruled as unconstitutional in earlier in the decision. The single dissenting vote (Judge O’Scannlain) relied on measure of total error, understood that there could be better methods available, but believed that Huntington-Hill minimized the variance from true size, and did not think there was enough evidence to overturn the current system used by Congress.
