Document ID: ./input/supremecourt_opinions/opinions/17pdf/16-402_h315.pdf
Page Number: 118.0

20 

CARPENTER v. UNITED STATES 

GORSUCH, J., dissenting 

nating  evidence.  Nagareda,  supra,  at  1605–1623;  Rex  v. 
Purnell, 96 Eng. Rep. 20 (K. B. 1748); Slobogin, Privacy at 
Risk 145 (2007). 

* 
What does all this mean for the case before us?  To start, 
I cannot fault the Sixth Circuit for holding that Smith and 
Miller  extinguish  any  Katz-based  Fourth  Amendment 
interest  in  third  party  cell-site  data.    That  is  the  plain
effect  of  their  categorical  holdings.  Nor  can  I  fault  the 
Court  today  for  its  implicit  but  unmistakable  conclusion
that the rationale of Smith and Miller is wrong; indeed, I
agree  with  that.    The  Sixth  Circuit  was  powerless  to  say
so, but this Court can and should.  At the same time, I do 
not  agree  with  the  Court’s  decision  today  to  keep  Smith 
and  Miller  on  life  support  and  supplement  them  with  a 
new and multilayered inquiry that seems to be only Katz-
squared.  Returning there, I worry, promises more trouble 
than  help.    Instead,  I  would  look  to  a  more  traditional 
Fourth  Amendment  approach.  Even  if  Katz  may  still
supply one way to prove a Fourth Amendment interest, it
has never been the only way.  Neglecting more traditional 
approaches  may  mean  failing  to  vindicate  the  full  protec-
tions of the Fourth Amendment. 

Our  case  offers  a  cautionary  example.  It  seems  to  me 
entirely  possible  a  person’s  cell-site  data  could  qualify  as 
his  papers  or  effects  under  existing  law.  Yes,  the  tele-
phone carrier holds the information.  But 47 U. S. C. §222 
designates  a  customer’s  cell-site  location  information  as
“customer  proprietary  network 
(CPNI),
§222(h)(1)(A), and gives customers certain rights to control 
use of and access to CPNI about themselves.  The statute 
generally  forbids  a  carrier  to  “use,  disclose,  or  permit
access  to  individually  identifiable”  CPNI  without  the 
customer’s  consent,  except  as  needed  to  provide  the  cus-
tomer’s  telecommunications  services.  §222(c)(1).    It  also 

information”