Document ID: ./input/supremecourt_opinions/opinions/18pdf/18-422_9ol1.pdf
Page Number: 58

Cite as:  588 U. S. ____ (2019) 

19 

KAGAN, J., dissenting 

actual precinct-level votes from past elections to determine
a  partisan  outcome  (i.e.,  the  number  of  Democratic  and 
Republican  seats  that  map  produces).  Suppose  we  now 
have  1,000  maps,  each  with  a  partisan  outcome  attached
to  it.  We  can  line  up  those  maps  on  a  continuum—the
most favorable to Republicans on one end, the most favor-
able  to  Democrats  on  the  other.3   We  can  then  find  the 
median  outcome—that  is,  the  outcome  smack  dab  in  the 
center—in  a  world  with  no  partisan  manipulation.  And 
we can see where the State’s actual plan falls on the spec-
trum—at  or  near  the  median  or  way  out  on  one  of  the
tails?  The  further  out  on  the  tail,  the  more  extreme  the 
partisan  distortion  and  the  more  significant  the  vote 
dilution.  See generally Brief for Eric S. Lander as Amicus 
Curiae 7–22. 

Using  that  approach,  the  North  Carolina  plaintiffs
offered  a  boatload  of  alternative  districting  plans—all 
showing  that  the  State’s  map  was  an  out-out-out-outlier. 
One  expert  produced  3,000  maps,  adhering  in  the  way
described  above  to  the  districting  criteria  that  the  North
Carolina  redistricting  committee  had  used,  other  than 
partisan advantage.  To calculate the partisan outcome of 
those maps, the expert also used the same election data (a 
composite  of  seven  elections)  that  Hofeller  had  employed 
when  devising  the  North  Carolina  plan  in  the  first  in-
stance.  The  results  were,  shall  we  say,  striking.    Every 
single one of the 3,000 maps would have produced at least 
one  more  Democratic  House  Member  than  the  State’s 
actual  map,  and  77%  would  have  elected  three  or  four 
more.  See Rucho, 318 F. Supp. 3d, at 875–876, 894; App. 

—————— 

3 As I’ll discuss later, this distribution of outcomes provides what the 
majority says does not exist—a neutral comparator for the State’s own 
plan.  See  ante,  at  16–19;  supra,  at  14;  infra,  at  22–25.    It  essentially 
answers  the  question:  In  a  State  with  these  geographic  features  and 
this  distribution  of  voters  and  this  set  of  districting  criteria—but 
without partisan manipulation—what would happen?