Document ID: ./input/supremecourt_opinions/opinions/17pdf/16-402_h315.pdf
Page Number: 53

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

3 

THOMAS, J., dissenting 

Olmstead  and  rejected  Fourth  Amendment  challenges  to
various methods of electronic surveillance.  See On Lee v. 
United  States,  343  U. S.  747,  749–753  (1952)  (use  of  mi­
crophone  to  overhear  conversations  with  confidential
informant); Goldman v. United States, 316 U. S. 129, 131– 
132,  135–136  (1942)  (use  of  detectaphone  to  hear  conver­
sations in office next door). 

In the 1960’s, however, the Court began to retreat from 
Olmstead.  In  Silverman  v.  United  States,  365  U. S.  505 
(1961),  for  example,  federal  officers  had  eavesdropped  on
the  defendants  by  driving  a  “spike  mike”  several  inches 
into the house they were occupying.  Id., at 506–507.  This 
was a “search,” the Court held, because the “unauthorized 
physical  penetration  into  the  premises”  was  an  “actual 
intrusion  into  a  constitutionally  protected  area.”    Id.,  at 
509,  512.  The  Court  did  not  mention  Olmstead’s  other 
holding  that  intangible  conversations  are  not  “persons,
houses,  papers,  [or]  effects.”  That  omission  was  signifi­
cant.  The  Court  confirmed  two  years  later  that  “[i]t  fol­
lows  from  [Silverman]  that  the  Fourth  Amendment  may 
protect  against  the  overhearing  of  verbal  statements  as
well as against the more traditional seizure of ‘papers and 
effects.’ ”    Wong  Sun  v.  United  States,  371  U. S.  471,  485 
(1963); accord, Berger v. New York, 388 U. S. 41, 51 (1967). 
In  Katz,  the  Court  rejected  Olmstead’s  remaining  hold-
ing—that eavesdropping is not a search absent a physical 
intrusion  into  a  constitutionally  protected  area.  The 
federal  officers  in  Katz  had  intercepted  the  defendant’s
conversations  by  attaching  an  electronic  device  to  the
outside of a public telephone booth.  389 U. S., at 348.  The 
Court  concluded  that  this  was  a  “search”  because  the 
officers  “violated  the  privacy  upon  which  [the  defendant] 
justifiably relied while using the telephone booth.”  Id., at 
353.  Although the device did not physically penetrate the 
booth,  the  Court  overruled  Olmstead  and  held  that  “the 
reach  of  [the  Fourth]  Amendment  cannot  turn  upon  the