Monday, September 16, 2019

Analyzing the "Non-Partisan" Legislative Districts in Mecklenburg County

With the approval of the proposed North Carolina State House and State Senate 'non-partisan' legislative maps, the North Carolina General Assembly is close to meeting its court-ordered redrawing of legislative districts for review by the three-judge superior court panel this week.

Much has been made about whether the new legislative districts in certain counties represent a truly 'non-partisan' redrawing of the maps, especially since the court order mandated that no electoral (read, partisan) data was to be used in the creation of the new districts.

There will be some debate over whether the 'base-line' maps (selected by random draws from the simulated maps provided by Dr. Chen) were non-partisan or not, but that is for the court to decide. However, those of us outside the legislative process do have partisan/electoral data at our disposal to analyze the precincts assigned to the proposed state house and senate districts.

While there are several counties that are being redrawn due to the court order, I decided to use Mecklenburg County to analyze their proposed state house and senate districts, due to the fact that Mecklenburg County gives their precinct election results with early votes (absentee one-stop, in particular) assigned back to the voter's respective precinct. Some counties (like Wake County) do not have their early votes publicly reassigned back to the precinct, make it harder to analyze a precinct's true electoral behavior (if anyone has a lead on how to get those precinct election returns to include early votes, please drop me an e-mail).

In analyzing Mecklenburg County's state house and senate districts, I used a common approach for analyzing a precinct's political 'behavior': a partisan voting index, or PVI. To construct a PVI, one takes a precinct's electoral performance and compares it against either the nation's, or state's, electorate performance for a party's candidate. I tend to use North Carolina state performance as the baseline in constructing this index.

For example, if a party's candidate received 48 percent of the state-wide vote in 2012, but in a precinct, that candidate received 58 percent of the vote, then the precinct is a +10 PVI. Then, in the 2016 election, the state-wide for a candidate remained at 48 percent, but the precinct went for that candidate with 68 percent, then the PVI would +20. I would then average the two PVIs, for an average PVI of +15 for either party (D+15 or R+15).

In general, one can think of PVIs as being how much more Democratic or Republican a particular district is in its voting behavior: a district that may be zero to +3 or 5 would be considered a competitive district, while one from +5 to 10 would be a potential 'lean' district to one party. A district with a PVI of greater than +10 would generally be considered a safe district.

In Mecklenburg County, the districts for the state house are:

And for Mecklenburg's state senate districts, the map is:

Taking the electoral returns for each of Mecklenburg's precincts and assigning them to their respective legislative district, I then constructed the PVIs, with special interest on the average of the 2012 and 2016 PVI for each district as a whole.

For Mecklenburg's State House delegation, the following districts have PVIs for 2012, 2016, and the average of the two (positive PVIs indicate Democratic-oriented performance, while negative PVIs are Republican-oriented performance of the district):

District: 2012 PVI 2016 PVI Average PVI
88 11% 14% 12%
92 28% 28% 28%
98 -9% -4% -6%
99 19% 19% 19%
100 25% 26% 25%
101 25% 25% 25%
102 32% 34% 33%
103 -1% 4% 1%
104 -3% 5% 1%
105 1% 7% 4%
106 33% 34% 34%
107 32% 33% 33%

Visually, Mecklenburg's State House districts' PVIs are:

In Mecklenburg County, eight of the twelve state house districts are Democratic safe districts, with only one being a 'lean' Republican district (the proposed 98th, located in north Mecklenburg) and 3 being competitive districts (the 103rd, 104th, and 105th, all in south Mecklenburg where the historic GOP 'wedge' of Charlotte and the county were located, but now a more competitive region). Currently, no Republicans are incumbents within Mecklenburg County's house delegation.

For Mecklenburg's State Senate delegation, the following districts have PVIs for 2012, 2016, and the average of the two:

District: 2012 PVI 2016 PVI Average PVI
37 1% 8% 4%
38 32% 33% 33%
39 10% 14% 12%
40 29% 29% 29%
41 6% 9% 8%

Visually, Mecklenburg's State Senate districts' PVIs are:

Only one of the five proposed Mecklenburg state senate districts could be considered 'competitive' (the 37th, in the south-eastern part of the county), while the other four range from lean Democratic (district 41 at a D+8, stretching from north Mecklenburg into very blue Charlotte precincts) to very safe Democratic (the 38th, drawn as a 'belt' across Mecklenburg, at an average PVI of D+33). Four of the five current districts are held by Democrats, with the sole Mecklenburg County Republican in the state general assembly (Dan Bishop) giving up his seat, due to his election to the Ninth Congressional District.

Ultimately, what we may be seeing is that no matter how the maps are drawn, especially due to the 'whole county' provision of the state constitution, partisanship will be quite evident due to the political 'sorting' that many precincts have experienced over the past few election cycles. As I've posted in early pieces, Mecklenburg County is undergoing a significant shift in political allegiance, driven mostly by Charlotte's deepening Democratic blues and the collapse of the Republican southern 'wedge' towards competitive precincts, as evident in the following PVI maps from 2004-08, 2008-12, and 2012-16 (yellow lines are Charlotte city council districts):

And as I have documented in a previous post, the relationship between the "top of the ballot" (presidential voting) down to state legislative races is a pretty close relationship; meaning that voters are more likely to be 'straight-ticket' voting down the ballot.

Of course, all of this may be moot by the time the court reviews the maps and considers whether they are still too partisan, in light of their decision, and asks for a special master to redraw the counties and the legislative districts. But for the time being, in at least one county, no matter if the maps are drawn for partisan favor or 'non-partisan,' partisanship will be present in the actions of the voters and reflected in the district lines.