The need for including fresh members arose after three of its members - Manish Tewari, Shashi Tharoor and Adhir Ranjan Chowdhury - became Union ministers in last month's reshuffle of the Council of Ministers.
A motion moved by JPC Chairman P C Chacko to appoint new members was passed in Lok Sabha by a voice vote amid din.
V Arun Kumar, Bhakta Charan Das and Pratap Singh Bajwa - all Congress- were appointed as the new members.
Recently, Chacko had said that he would move a fresh motion seeking yet another extension for JPC as its term ends in December.
This will be the fourth extension of the committee set up in March last year. The panel, which has so far taken evidence from top serving and former government officials, investigation agencies and CAG, is mandated to examine policy prescriptions and their interpretation by successive governments and to examine irregularities and aberrations in the implementation of government decisions between 1998 and 2009.