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Page Number: 57.0

18 

RUCHO v. COMMON CAUSE 

KAGAN, J., dissenting 

too far.  Consider again Justice Kennedy’s hypothetical of 
mapmakers  who  set  out  to  maximally  burden  (i.e.,  make 
count  for  as  little  as  possible)  the  votes  going  to  a  rival 
party.  See  supra,  at  12.  Does  the  majority  really  think 
that goal is permissible?  But why even bother with hypo-
theticals?  Just  consider  the  purposes  here.    It  cannot  be 
permissible  and  thus  irrelevant,  as  the  majority  claims, 
that  state  officials  have  as  their  purpose  the  kind  of  gro-
tesquely  gerrymandered  map  that,  according  to  all  this 
Court has ever said, violates the Constitution.  See supra, 
at 13. 

On  to  the  second  step  of  the  analysis,  where  the  plain-
tiffs  must  prove  that  the  districting  plan  substantially
dilutes  their  votes.    The  majority  fails  to  discuss  most  of
the evidence the District Courts relied on to find that the 
plaintiffs  had  done  so.  See  ante,  at  23–24.    But  that  evi-
dence—particularly  from  North  Carolina—is  the  key  to 
understanding  both  the  problem  these  cases  present  and 
the solution to it they offer.  The evidence reveals just how 
bad  the  two  gerrymanders  were  (in  case  you  had  any 
doubts).  And it shows how the same technologies and data
that  today  facilitate  extreme  partisan  gerrymanders  also 
enable courts to discover them, by exposing just how much
they dilute votes.  See Vieth, 541 U. S., at 312–313 (opin-
ion of Kennedy, J.) (predicting that development). 

Consider  the  sort  of  evidence  used  in  North  Carolina 
first.  There,  the  plaintiffs  demonstrated  the  districting
plan’s  effects  mostly  by  relying  on  what  might  be  called
the  “extreme  outlier  approach.”    (Here’s  a  spoiler:  the 
State’s  plan  was  one.)  The  approach—which  also  has 
recently  been  used  in  Michigan  and  Ohio  litigation—
begins  by  using  advanced  computing  technology  to  ran-
domly  generate  a  large  collection of  districting  plans  that 
incorporate  the  State’s  physical  and  political  geography 
and meet its declared districting  criteria, except for parti-
san  gain.  For  each  of  those  maps,  the  method  then  uses