Document ID: ./input/supremecourt_opinions/opinions/17pdf/16-402_h315.pdf
Page Number: 23.0

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

19 

Opinion of the Court 

material  to  an  ongoing  investigation.” 
18  U. S. C. 
§2703(d).  That  showing  falls  well  short  of  the  probable 
cause required for a warrant.  The Court usually requires 
“some  quantum  of 
individualized  suspicion”  before 
a  search  or  seizure  may  take  place.    United  States  v. 
Martinez-Fuerte, 428 U. S. 543, 560–561 (1976).  Under the 
standard in the Stored Communications Act, however, law 
enforcement  need  only  show  that  the  cell-site  evidence
might be pertinent to an ongoing investigation—a “gigan-
tic”  departure  from  the  probable  cause  rule,  as  the  Gov-
ernment  explained  below.  App.  34.    Consequently,  an
order  issued  under  Section  2703(d)  of  the  Act  is  not  a
permissible  mechanism  for  accessing  historical  cell-site
records.  Before compelling a wireless carrier to turn over
a  subscriber’s  CSLI,  the  Government’s  obligation  is  a 
familiar one—get a warrant. 

JUSTICE  ALITO  contends  that  the  warrant  requirement 
simply  does  not  apply  when  the  Government  acquires
records  using  compulsory  process.    Unlike  an  actual 
search,  he  says,  subpoenas  for  documents  do  not  involve
the direct taking of evidence; they are at most a “construc-
tive search” conducted by the target of the subpoena.  Post, 
at  12.  Given  this  lesser  intrusion  on  personal  privacy, 
JUSTICE  ALITO  argues  that  the  compulsory  production  of
records  is  not  held  to  the  same  probable  cause  standard.
In his view, this Court’s precedents set forth a categorical 
rule—separate  and  distinct  from  the  third-party  doc-
trine—subjecting  subpoenas  to  lenient  scrutiny  without 
regard  to  the  suspect’s  expectation  of  privacy  in  the  rec-
ords.  Post, at 8–19. 

But this Court has never held that the Government may
subpoena  third  parties  for  records  in  which  the  suspect 
has a reasonable expectation of privacy.  Almost all of the 
examples JUSTICE ALITO cites, see post, at 14–15, contem-
plated  requests  for  evidence  implicating  diminished  pri-