In 1949, he sponsored the Feinberg Bill, an act to purge communist and fellow traveler teachers from the state public-school system.
[1] The bill required the Regents of the State School Board to draw up a list of all subversive organizations.
Although the law focused on organizational membership, in its implementation it would delve into people's reading preferences, social activities, rallies attended, petitions signed, and beliefs on current political issues.
[4] On March 30, 1949, Feinberg was appointed chairman of the New York State Public Service Commission, and remained in office until 1958.
Feinberg was instrumental in the founding of the State University of New York,[citation needed] and the library at SUNY Plattsburgh is named after him.