Document ID: ./input/supremecourt_opinions/opinions/17pdf/16-402_h315.pdf
Page Number: 55.0

Cite as:  585 U. S. ____ (2018) 

5 

THOMAS, J., dissenting 

(“We  propose  a  test  using  a  way  that’s  not  too  dissimilar
from the tort ‘reasonable man’ test”).  After some question­
ing  from  the  Justices,  the  lawyer  conceded  that  his  test 
should  also  require  individuals  to  subjectively  expect 
privacy.  See  id.,  at  12.  With  that  modification,  Justice 
Harlan seemed to accept the lawyer’s test almost verbatim 
in his concurrence. 

Although the majority opinion in Katz had little practi­
cal  significance  after  Congress  enacted  the  Omnibus
Crime  Control  and  Safe  Streets  Act  of  1968,  Justice  Har­
lan’s  concurrence  profoundly  changed  our  Fourth  Amend­
ment  jurisprudence. 
It  took  only  one  year  for  the  full 
Court  to  adopt  his  two-pronged  test.    See  Terry  v.  Ohio, 
392  U. S.  1,  10  (1968).   And  by  1979,  the  Court  was  de­
scribing  Justice  Harlan’s  test  as  the  “lodestar”  for  deter­
mining whether a “search” had occurred.  Smith v. Mary-
land,  442  U. S.  735,  739  (1979).    Over  time,  the  Court 
minimized  the  subjective  prong  of  Justice  Harlan’s  test.
See  Kerr,  Katz  Has  Only  One  Step:  The  Irrelevance  of 
Subjective  Expectations,  82  U. Chi.  L. Rev.  113  (2015).
That left the objective prong—the “reasonable expectation
of  privacy”  test  that  the  Court  still  applies  today.    See 
ante,  at  5;  United  States  v.  Jones,  565  U. S.  400,  406 
(2012). 

II
  Under  the  Katz  test,  a  “search”  occurs  whenever  “gov­
ernment officers violate a person’s ‘reasonable expectation
of privacy.’ ”  Jones, supra, at 406.  The most glaring prob­
lem with this test is that it has “no plausible foundation in 
the text of the Fourth Amendment.”  Carter, 525 U. S., at 
97  (opinion  of  Scalia,  J.).    The  Fourth  Amendment,  as 
relevant  here,  protects  “[t]he  right  of  the  people  to  be 
secure  in  their  persons,  houses,  papers,  and  effects, 
against  unreasonable  searches.”    By  defining  “search”  to
mean  “any  violation  of  a  reasonable  expectation  of  pri-