Document ID: ./input/supremecourt_opinions/opinions/17pdf/16-402_h315.pdf
Page Number: 65.0

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

15 

THOMAS, J., dissenting 

§222  “protects  the  interests  of  individuals  against  wrong­
ful  uses  or  disclosures  of  personal  data,  the  rationale  for 
these legal protections has not historically been grounded
on  a  perception  that  people  have  property  rights  in  per­
sonal  data  as  such.”  Samuelson,  Privacy  as  Intellectual 
Property?  52  Stan.  L.  Rev.  1125,  1130–1131  (2000)  (foot­
note  omitted).  Any  property  rights  remain  with  the 
companies. 

E 
The  Katz  test  comes  closer  to  the  text  of  the  Fourth 
Amendment  when  it  asks  whether  an  expectation  of  pri- 
vacy is “reasonable,” but it ultimately distorts that term as
well.  The  Fourth  Amendment  forbids  “unreasonable 
searches.”  In other words, reasonableness determines the 
legality  of  a  search,  not  “whether  a  search  . . .  within  the 
meaning  of  the  Constitution  has  occurred.”  Carter,  525 
U. S.,  at  97  (opinion  of  Scalia,  J.)  (internal  quotation 
marks omitted). 
  Moreover,  the  Katz  test  invokes  the  concept  of  reason- 
ableness in a way that would be foreign to the ratifiers of 
the  Fourth  Amendment.    Originally,  the  word  “unreason- 
able”  in  the  Fourth  Amendment  likely  meant  “against 
reason”—as  in  “against  the  reason  of  the  common  law.”
See  Donahue  1270–1275;  Davies  686–693;  California  v. 
Acevedo,  500  U. S.  565,  583  (1991)  (Scalia,  J.,  concurring
in judgment).  At the founding, searches and seizures were 

—————— 

But  this  order  was  vacated  by  the  Court  of  Appeals  for  the  Tenth 
Circuit.  U. S. West, Inc. v. FCC, 182 F. 3d 1224, 1240 (1999).  Notably,
the  carrier  in  that  case  argued  that  the  FCC’s  regulation  of  customer 
information  was  a  taking  of  its  property.  See  id.,  at  1230.    Although
the panel majority had no occasion to address this argument, see id., at 
1239,  n. 14,  the  dissent  concluded  that  the  carrier  had  failed  to  prove 
the information was “property” at all, see id., at 1247–1248 (opinion of 
Briscoe, J.).