[1][2] He was educated at Cheddipalayam Maha Vidyalayam and St. Michael's College National School.
[2] Following the Black July anti-Tamil riots he left school in August 1983 and in November 1983 he joined Tamil Eelam Liberation Organization (TELO), a Tamil militant group.
[4] He contested the 2012 provincial council election as one of the Tamil National Alliance (TNA) electoral alliance's candidates in Batticaloa District and was elected to the Eastern Provincial Council.
[5] Karunakaran and the other newly elected TNA provincial councillors took their oaths on 28 September 2012 in front of TNA leader and Member of Parliament R.
[7][8] He contested the 2020 parliamentary election as a TNA candidate in Batticaloa District and was re-elected to the Parliament of Sri Lanka.