Analysis of Court Drawn Council Map Shows Indianapolis Republicans Have Nowhere to Go for a Majority

I spent some time crunching the numbers to ascertain the partisanship leanings of the non-partisan maps produced at the direction of the Marion County Superior Court.   The courts' order, which outlines which precincts will be in which districts, is available here.

First, a caveat.  The data I used to establish my baseline is the 2012 Marion County Surveyor's race.  While you always look for a low profile race, I would have liked to use 2010 data given the turnout in such a midterm election is closer to the turnout in a municipal election. However, due to the reprecincting after the 2010 election, I would have needed an expensive computer program to convert that 2010 election data, ran under pre-2010 precincts to the post-2010 precincts.  Still the 2012 data is not without advantages.  2010 was an exceptionally good Republican year which doesn't reflect a typical year. Plus, 2012 data is newer and thus would incorporate some of the more recent population shifts.

When the map by Republican operative David Brooks was put together in 2011, he provided summaries purportedly showing that, using the 2010 data, the Republican party would have a majority in 15 of the 25 council districts.  I questioned whether that was possible given the growing Democratic majority in Marion County. Indeed when I ran the Brooks map using the 2012 election numbers, I found dramatic reductions in the Republican baseline in virtually every district from 2010 (as claimed by Brooks) to 2012, so much so that the Democrats had a 17-8 majority under the Brooks map.

The good news for the GOP is that there are more Republican districts in the Marion County Superior Court map than the one drawn by Brooks.  According to my analysis, again, using 2012 election data, the Democratic majority, as measured by the baseline in each district is 15-10.

Unfortunately for Republicans that is the only good news about the judicially-drawn map.  Republicans have five districts (3, 4, 5, 17 and 19) which only lean (less than 6 point spread) Republican.   The margin between the partisan baselines in those districts is only 3.2, 2.6, 3.6, 2.8 and 1.8 respectively.   Districts 3, 4 and 5 are districts in eastern Washington Township and Lawrence Township.  District 17 is in the Irvington area while District 19 is at the corner where four townships (Center, Perry, Wayne and Decatur come together). My guess is that these leaning Republican districts will prove to be more Republican in the low turnout municipal election year.

Meanwhile the Democrats have no close districts to defend.   District 12, which sets on the far west side of Wayne Township is a moderately competitive Democratic district with an 8 point spread.  Meanwhile Republicans have a moderately competitive district, District 24 (northern Perry Township) that has a baseline margin of 10.4 points.


That's it for election competition.   The rest of the districts are noncompetitive, i.e. more than a 15 point spread between the two baselines, and often much, much more than that.   Republicans have 4 solidly GOP districts (18, 22, 23, and 25) all on the southside.  Their margins are, respectively 16.0, 23.4, 23.8 and 19.5.  Democrats meanwhile have 14 solidly Democratic districts (1, 2, 6, 7, 8, 9, 10, 11, 14, 15, 16, 18, 20, 21) that respectively have margins of 34.4, 24.6, 32.0, 65.2, 45.3 54.6, 59.2, 42.8, 76.4, 74.2, 77.4, 16.0, 40.0, 22.0.

In summary, there are only 7 council districts that are close or moderately competitive and 6 are those are Republican baseline seats.  Eighteen of the districts are non-competitive, some spectacularly uncompetitive.  The maximum number of seats Republicans can win on this map is ten, eleven if everything breaks right and they win District 12.  If it is a bad Republican year, the Democrats on the high end could end up winning as many as 20 districts.

Here is the table showing my analysis.

Dist	D	R	Total	D%	R%	Spread	Party
1	11328	5518	16,846	67.2	32.8	34.4	SD
2	9561	5749	15,310	62.4	37.6	24.6	SD
3	8308	8870	17,148	48.4	51.6	3.2	LR
4	8248	8698	16,946	48.7	51.3	2.6	LR
5	8144	8760	16,904	48.2	51.8	3.6	LR
6	8790	4536	13,326	66.0	34.0	32.0	SD
7	10,750	2192	12,942	83.1	17.9	65.2	SD
8	13,418	5033	18,451	72.7	27.3	45.3	SD
9	13,722	4024	17,746	77.3	22.7	54.6	SD
10	8518	2179	10,697	79.6	20.4	59.2	SD
11	9488	3807	13,295	71.4	28.6	42.8	SD
12	6809	5790	12,599	54.0	46.0	8.0	MD
13	5893	4329	10,222	57.7	42.3	15.4	SD
14	9624	1284	10,908	88.2	11.8	76.4	SD
15	14,750	2192	16,942	87.1	12.9	74.2	SD
16	12,376	1569	13,945	88.7	11.3	77.4	SD
17	7730	8183	15,913	48.6	51.4	2.8	LR
18	4619	6372	10,991	42.0	58.0	16.0	SR
19	4218	4378	8596	49.1	50.9	1.8	LR
20	5798	2304	8102	70.0	30.0	40.0	SD
21	5341	3421	8762	61.0	39.0	22.0	SD
22	5544	8926	14,470	38.3	61.7	23.4	SR
23	5597	9079	14,676	38.1	61.9	23.8	SR
24	4871	5996	10,867	44.8	55.2	10.4	MR
25	4817	7140	11,957	40.3	59.7	19.4	SR