Document ID: ./input/supremecourt_opinions/opinions/12pdf/11-1425_cb8e.pdf
Page Number: 5

Cite as:  569 U. S. ____ (2013) 

1 

Opinion of the Court 

NOTICE:  This opinion is subject to formal revision before publication in the
preliminary  print  of  the  United  States  Reports.  Readers  are  requested  to
notify the Reporter of Decisions, Supreme Court of the United States, Wash­
ington,  D. C.  20543,  of  any  typographical  or  other  formal  errors,  in  order
that corrections may be made before the preliminary print goes to press. 

SUPREME COURT OF THE UNITED STATES 

_________________ 

No. 11–1425 
_________________ 

MISSOURI, PETITIONER v. TYLER G. MCNEELY 

ON WRIT OF CERTIORARI TO THE SUPREME COURT OF
 
MISSOURI
 

[April 17, 2013] 

JUSTICE  SOTOMAYOR  announced  the  judgment  of  the
Court and delivered the opinion of the Court with respect 
to Parts I, II–A, II–B, and IV, and an opinion with respect 
to  Parts  II–C  and  III,  in  which  JUSTICE  SCALIA,  JUSTICE 
GINSBURG, and JUSTICE KAGAN join. 

In  Schmerber  v.  California,  384  U. S.  757  (1966),  this
Court  upheld  a  warrantless  blood  test  of  an  individual
arrested for driving under the influence of alcohol because 
the  officer  “might  reasonably  have  believed  that  he  was
confronted  with  an  emergency,  in  which  the  delay  neces­
sary to obtain a warrant, under the circumstances, threat­
ened  the  destruction  of  evidence.”    Id.,  at  770  (internal
quotation  marks  omitted).  The  question  presented  here
is  whether  the  natural  metabolization  of  alcohol  in  the 
bloodstream  presents  a  per se  exigency  that  justifies  an 
exception  to  the  Fourth  Amendment’s  warrant  require­
ment for nonconsensual blood testing in all drunk-driving 
cases.  We  conclude  that  it  does  not,  and  we  hold,  con­
sistent  with  general  Fourth  Amendment  principles,  that
exigency  in  this  context  must  be  determined  case  by  case
based on the totality of the circumstances.