Document ID: ./input/supremecourt_opinions/opinions/17pdf/16-402_h315.pdf
Page Number: 46

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

19 

KENNEDY, J., dissenting 

Perhaps more important, those future developments are
no  basis  upon  which  to  resolve  this  case.    In  general,  the
Court  “risks  error  by  elaborating  too  fully  on  the  Fourth
Amendment implications of emerging technology before its
role  in  society  has  become  clear.”    Ontario  v.  Quon,  560 
U. S.  746,  759  (2010).    That  judicial  caution,  prudent  in
most cases, is imperative in this one. 

Technological  changes  involving  cell  phones  have  com-
plex  effects  on  crime  and  law  enforcement.    Cell  phones
make  crimes  easier  to  coordinate  and  conceal,  while  also 
providing  the  Government  with  new  investigative  tools
that  may  have  the  potential  to  upset  traditional  privacy
expectations. 
See  Kerr,  An  Equilibrium-Adjustment
Theory  of  the  Fourth  Amendment,  125  Harv.  L. Rev  476, 
512517  (2011).  How  those  competing  effects  balance
against each other, and how property norms and expecta-
tions of privacy form around new technology, often will be
difficult to determine during periods of rapid technological
change.  In those instances, and where the governing legal
standard  is  one  of  reasonableness,  it  is  wise  to  defer  to 
legislative judgments like the one embodied in §2703(d) of 
the Stored Communications Act.  See Jones, 565 U. S., at 
430 (ALITO, J., concurring).  In §2703(d) Congress weighed
the privacy interests at stake and imposed a judicial check 
to prevent executive overreach.  The Court should be wary
of upsetting that legislative balance and erecting constitu-
tional  barriers  that  foreclose  further  legislative  instruc-
tions.  See Quon, supra, at 759.  The last thing the Court
should do is incorporate an arbitrary and outside limit—in 
this case six days’ worth of cell-site records—and use it as
the  foundation  for  a  new  constitutional  framework.   The 
Court’s  decision  runs  roughshod  over  the  mechanism
Congress put in place to govern the acquisition of cell-site
records  and  closes  off  further  legislative  debate  on  these
issues.