While I wait for the LRC to post the text of the truckload of new bills whose titles they published yesterday, I’m musing over Legislative district demographics.
As of 11 a.m. this morning, the average number of registered voters in each of our 35 Legislative districts is 15,116. Actual registered voters range from 11,077 in District 15 (central Sioux Falls) to 19,038 in District 33 (north and west edges of Rapid City, Black Hawk, Summerset, then west out into the Hills around Johnson Siding and Pactola).
Districts are supposed to include a roughly equal population. In 2010, that ideal population would have been 23,262. Based on the 2016 Census estimate, fair Legislative districts would each include 24,727 South Dakotans.
According to the Census, 75.4% of South Dakota’s population is 18 or older. That means that, in an ideally drawn district, we should find 18,644 voting-age residents. Some small percentage of those folks would be unable to vote due to felony convictions (although once you’ve served your full sentence, you can register to vote again!) or lack of citizenship, but we won’t get that deep into the numbers.
Comparing the 2016 population estimate with current vote registration, we find that 81.07% of voting-age South Dakotans appear to be registered to vote. Yet in four districts (15, 7, 26, and 17), the ratio of registered voters to ideal voting-age population is less than 70%. In six districts (8, 12, 14, 11, 30, and 33) the ratio of registered voters to ideal voting-age population is greater than 90%.
|District||Active Registered Voters 2018.01.03||Active/ Ideal2016||Difference from average participation (% pts)|
The seeming voter deficit in District 15 could be accounted for entirely by the penitentiary population. Subtract those 1,500-some inmates from District 15’s estimated voting-age population, and District 15’s active/ideal ratio jumps a hair above the statewide average.
The deficits in 7 and 17—Brookings and Vermillion/Clay and Turner counties) may related to the university populations boosting Census count but depressing voter registration, as students either don’t vote or vote back home. The smaller university populations of Aberdeen, Spearfish, and Madison don’t appear to have the same impact on their district ratios: NSU’s District 3 is just one percentage point below the state average, while BHSU’s 31 and DSU’s 8 are both several points above the average.
Overall, the numbers could reflect shifting populations. A lower-than-average active/ideal participation ratios could signal a decline the district’s population since 2010. A higher-than-average active/ideal participation ratio could mean lots of people have moved into the district since 2010. If that’s the case, low-participation districts like 35 (East Rapid) need to be drawn bigger when we redistrict in 2021, while districts like neighboring 30 and 33 need to be drawn smaller to restore population balance.
If these voter registration patterns remain steady in the 2018 election, and if we assume equal turnout rates in all districts, then one voter in District 15 voting to reëlect Senator Reynold Nesiba has 36% more power than a voter in District 2 voting to reëlect Senator Brock Greenfield and 72% more power than one voter in District 33 voting to reëlect Senator Phil Jensen.
So here’s something to think about: should we draw Legislative district boundaries with an eye toward actual voting populations? Or would such math disadvantage districts with large populations who need representations (children and inmates are people, too) but who can’t vote?