@ScreenName48105, how admissions is done differs a lot by school. Some do hand it off to a school/college/department to decide. At other places, it is done by the admissions committee.
At Oxbridge, the final decision is definitely made by faculty members of a department. At Cornell, by the different colleges. At most elites, the admissions committee (which may include faculty) make the call. At Northwestern, Admissions decides on applicants to Engineering and Arts&Sciences, but Music chooses its students, Journalism chooses its students, etc.