Document ID: ./input/supremecourt_opinions/opinions/boundvolumes/558bv.pdf
Page Number: 226.0

Cite as: 558 U. S. 53 (2009) 

65 

Kennedy, J., concurring 

not  been  fully  explicated  in  prior  decisions,  it  seems  to  me 
that the State can establish a new baseline without later hav­
ing  its  procedural  bar  ignored  by  the  federal  courts.  This 
should be true even if the principles barring the postverdict 
motions are ﬁrst elaborated in the instant case. 

The  process  of  elaborating,  deﬁning,  and  then  shaping  a 
State’s decisional  law after  considering the  competing argu­
ments  in  a  speciﬁc  case  rests  on  this  premise:  Novel  facts 
and  circumstances  may  disclose  principles  that,  while  con­
sistent  with  the  logic  and  rationality  the  law  seeks  and  in 
that  sense  predictable,  still  have  not  yet  been  deﬁned  with 
precision  in  earlier  cases.  This  is  the  dynamic  of  the  case 
system we rely upon to explain the law. 

The adequate state ground doctrine ought not to foreclose 
the  case  process  in  the  separate  States.  A  too-rigorous  or 
demanding  insistence  that  procedural  requirements  be  es­
tablished in all of their detail before they can be given effect 
in  federal  court  would  deprive  the  States  of  the  case  law 
decisional  dynamic  that  the  Judiciary  of  the  United  States 
ﬁnds necessary and appropriate for the elaboration of its own 
procedural rules.  See, e. g., Smith v.  United States, 94 U. S. 
97 (1876).  Save where there is exclusive jurisdiction or fed­
eral  supremacy,  a  proper  constitutional  balance  ought  not 
give federal courts latitude in the interpretation and elabora­
tion of its law that it then withholds from the States.  There 
is no sense in applying the adequate state ground rule with­
out its being informed by these principles. 

Whether  the  structure  of  this  case  either  permits  or  re­
quires  consideration  of  these  matters  is  not  clear  at  this 
stage.  In a proper case, however, these concerns should be 
addressed.  It  seems  most  doubtful  that  this  Court  can  or 
should require federal courts to disregard a state procedural 
ground  that  was  not  in  all  respects  explicit  before  the  case 
when  it  was  ﬁrst  announced,  absent  a  showing  of  a  purpose 
or  pattern  to  evade  constitutional  guarantees.  And  this  is 
particularly so when the state procedural requirement arose