Document ID: ./input/supremecourt_opinions/opinions/12pdf/11-1425_cb8e.pdf
Page Number: 41.0

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

1 

THOMAS, J., dissenting 

SUPREME COURT OF THE UNITED STATES 

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No. 11–1425 
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MISSOURI, PETITIONER v. TYLER G. MCNEELY 

ON WRIT OF CERTIORARI TO THE SUPREME COURT OF 

MISSOURI
 

[April 17, 2013] 

JUSTICE THOMAS, dissenting. 
This  case  requires  the  Court  to  decide  whether  the
Fourth  Amendment  prohibits  an  officer  from  obtaining  a 
blood  sample  without  a  warrant  when  there  is  probable
cause to believe that a suspect has been driving under the
influence  of  alcohol.  Because  the  body’s  natural  meta­
bolization  of  alcohol  inevitably  destroys  evidence  of  the 
crime, it constitutes an exigent circumstance.  As a result, I 
would hold that a warrantless blood draw does not violate 
the Fourth Amendment. 

I 

A 

The  Fourth  Amendment  states  that  “[t]he  right  of  the
people to be secure in their persons . . . against unreason­
able  searches  and  seizures,  shall  not  be  violated,  and  no 
Warrants shall issue, but upon probable cause.”  Before a 
search  occurs,  “a  warrant  must  generally  be  secured,” 
Kentucky v. King, 563 U. S. ___, ___ (2011) (slip op., at 5), 
but  “this  presumption  may  be  overcome  in  some  circum­
stances  because  ‘[t]he  ultimate  touchstone  of  the  Fourth 
Amendment  is  “reasonableness.”  ’ ”  Ibid.  (quoting  Brig­
ham  City  v.  Stuart,  547  U. S.  398,  403  (2006);  alteration 
in original).

The  presence  of  “exigent  circumstances”  is  one  such
exception  to  the  warrant  requirement.  Exigency  applies