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Page Number: 56

6 

CARPENTER v. UNITED STATES 

THOMAS, J., dissenting 

vacy,”  the  Katz  test  misconstrues  virtually  every  one  of 
these words. 

A 
The  Katz  test  distorts  the  original  meaning  of 
“searc[h]”—the  word  in  the  Fourth  Amendment  that  it
purports to define, see ante, at 5; Smith, supra.  Under the 
Katz  test,  the  government  conducts  a  search  anytime  it
violates  someone’s  “reasonable  expectation  of  privacy.” 
That is not a normal definition of the word “search.” 

At  the  founding,  “search”  did  not  mean  a  violation  of 
someone’s  reasonable  expectation  of  privacy.   The  word 
was  probably  not  a  term  of  art,  as  it  does  not  appear  in 
legal dictionaries from the era.  And its ordinary meaning 
was the same as it is today: “ ‘[t]o look over or through for 
the  purpose  of  finding  something;  to  explore;  to  examine
by inspection; as, to search the house for a book; to search 
the wood for a thief.’ ”  Kyllo v. United States, 533 U. S. 27, 
32, n. 1 (2001) (quoting N. Webster, An American Diction­
ary  of  the  English  Language  66  (1828)  (reprint  6th  ed. 
1989));  accord,  2  S.  Johnson,  A  Dictionary  of  the  English
Language  (5th  ed.  1773)  (“Inquiry  by  looking  into  every 
suspected  place”);  N.  Bailey,  An  Universal  Etymological
English  Dictionary  (22d  ed.  1770)  (“a  seeking  after,  a 
looking  for,  &c.”);  2  J.  Ash,  The  New  and  Complete  Dic­
tionary  of  the  English  Language  (2d  ed.  1795)  (“An  en­
quiry,  an  examination,  the  act  of  seeking,  an  enquiry  by 
looking into every suspected place; a quest; a pursuit”); T. 
Sheridan, A Complete Dictionary of the English Language 
(6th ed. 1796) (similar).  The word “search” was not asso­
ciated  with  “reasonable  expectation  of  privacy”  until  Jus­
tice  Harlan  coined  that  phrase  in  1967.    The  phrase  “ex­
pectation(s)  of  privacy”  does  not  appear  in  the  pre-Katz 
federal  or  state  case  reporters,  the  papers  of  prominent