Histories of struggles over the right to privacy in the United States follow a path
from concerns over the postal system, through the anxieties created by new
photographic technology and the behavior of the sensational press at the turn of
the twentieth century, to debates over wiretapping that culminated in the
Supreme Court’s Olmstead v. US decision in 1928 upholding the government’s
right to collect evidence by that means. Missing from those accounts are efforts
to regulate surveillance and protect privacy focused on the private detectives who
undertook much of the activity that worried early-twentieth-century Americans.
In particular, these years saw the development of licensing regimes to restrict
who could conduct surveillance and provide a means of taking action against
those activities intruded too far into their subjects’ privacy. This paper will
explore the practices of private detectives and consider what impact licensing had
on those practices, and on evolving ideas of a right to privacy.