Document ID: ./input/supremecourt_opinions/opinions/17pdf/16-402_h315.pdf
Page Number: 111.0

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

13 

GORSUCH, J., dissenting 

the Fourth Amendment”).

Beyond  its  provenance  in  the  text  and  original  under-
standing  of  the  Amendment,  this  traditional  approach
comes  with  other  advantages.  Judges  are  supposed  to
decide cases based on “democratically legitimate sources of 
law”—like  positive  law  or  analogies  to  items  protected  by 
the  enacted  Constitution—rather  than  “their  own  biases 
or personal policy preferences.”  Pettys, Judicial Discretion
in Constitutional Cases, 26 J. L. & Pol. 123, 127 (2011).  A 
Fourth  Amendment  model  based  on  positive  legal  rights
“carves out significant room for legislative participation in 
the  Fourth  Amendment  context,”  too,  by  asking  judges  to 
consult  what  the  people’s  representatives  have  to  say 
about  their  rights.    Baude  &  Stern,  129  Harv.  L. Rev.,  at 
1852.  Nor is this approach hobbled by  Smith  and Miller, 
for  those  cases  are  just  limitations  on  Katz,  addressing
only  the  question  whether  individuals  have  a  reasonable 
expectation  of  privacy  in  materials  they  share  with  third
parties.  Under  this  more  traditional  approach,  Fourth
Amendment protections for your papers and effects do not 
automatically disappear just because you share them with
third parties.

Given the prominence Katz has claimed in our doctrine, 
American  courts  are  pretty  rusty  at  applying  the  tradi-
tional approach to the Fourth Amendment.  We know that 
if  a  house,  paper,  or  effect  is  yours,  you  have  a  Fourth 
Amendment  interest  in  its  protection.  But  what  kind  of 
legal interest is sufficient to make something yours?  And 
what  source  of  law  determines  that?    Current  positive 
law?  The  common  law  at  1791,  extended  by  analogy  to 
modern  times?  Both?  See  Byrd,  supra,  at  ___–___  (slip 
op.,  at  1–2)  (THOMAS, J.,  concurring);  cf.  Re,  The  Positive 
Law  Floor,  129  Harv.  L.  Rev.  Forum  313  (2016).    Much 
work  is  needed  to  revitalize  this  area  and  answer  these 
questions.  I  do  not  begin  to  claim  all  the  answers  today,
but  (unlike  with  Katz)  at  least  I  have  a  pretty  good  idea