Question

After the president appoints a new supreme court justice which committee

Answer 1

Candidates are nominated by the President of the United States and must face a series of hearings in which both the nominee and other witnesses make statements and answer questions before the Senate Judiciary Committee, which can vote to send the nomination to the full United States Senate.

Answer 2

After the president appoints a new supreme court justice  the committee that holds hearings to consider the qualifications of the appointee is: the Senate Judiciary Committee
The senate judiciary committee has 20 members in it and they are responsible for arranging the hearing of the acceptance process of the newly appointed supreme court justice