Document ID: ./input/supremecourt_opinions/opinions/boundvolumes/558bv.pdf
Page Number: 202.0

Cite as: 558 U. S. 30 (2009) 

41 

Per Curiam 

So. 2d 908, 910 (Fla. 1975) (per curiam).  Porter must show 
that  but  for  his  counsel’s  deﬁciency,  there  is  a  reasonable 
probability he would have received a different sentence.  To 
assess that probability, we consider “the totality of the avail­
able mitigation evidence—both that adduced at trial, and the 
evidence adduced in the habeas proceeding”—and “reweig[h] 
it  against  the  evidence  in  aggravation.”  Williams,  supra, 
at 397–398. 

This is not a case in which the new evidence “would barely 
have altered the sentencing proﬁle presented to the sentenc­
ing judge.”  Strickland, supra, at 700.  The judge and jury 
at  Porter’s  original  sentencing  heard  almost  nothing  that 
would  humanize  Porter  or  allow  them  to  accurately  gauge 
his  moral  culpability.  They  learned  about  Porter’s  turbu­
lent relationship with Williams, his crimes, and almost noth­
ing else.  Had Porter’s counsel been effective, the judge and 
jury would have learned of the “kind of troubled history we 
have  declared relevant  to  assessing  a defendant’s  moral  cul­
pability.”  Wiggins, supra, at 535.  They would have heard 
about (1)  Porter’s heroic military  service in two of  the most 
critical—and  horriﬁc—battles  of  the  Korean  War,  (2)  his 
struggles  to  regain  normality  upon  his  return  from  war, 
(3)  his  childhood  history  of  physical  abuse,  and  (4)  his  brain 
abnormality,  difﬁculty  reading  and  writing,  and  limited 
schooling.  See  Penry  v.  Lynaugh,  492  U. S.  302,  319  (1989) 
(“ ‘[E]vidence  about  the  defendant’s  background  and  char­
acter is relevant because of the belief, long held by this soci­
ety,  that  defendants  who  commit  criminal  acts  that  are  at­
tributable  to  a  disadvantaged  background  .  .  .  may  be  less 
culpable’ ”).  Instead, they heard absolutely none of that evi­
dence, evidence which “might well have inﬂuenced the jury’s 
appraisal  of  [Porter’s]  moral  culpability.”  Williams,  supra, 
at 398. 

On  the  other  side  of  the  ledger,  the  weight  of  evidence 
in  aggravation  is  not  as  substantial  as  the  sentencing  judge 
thought.  As noted, the sentencing judge accepted the jury’s