[2][3][4] His father had been a print journalist in Sri Lanka, and worked at The Dominion Post after moving to New Zealand, so news and current affairs was a constant component of Casinader's home life and upbringing.
[7][6] He then began writing for youth magazine Tearaway, which gave him the opportunity at the age of 15 to interview then Prime Minister Helen Clark.
[1][6] Casinader studied Bachelor of Arts (majoring in Public Policy and International Relations) at Victoria University of Wellington.
[1][8] After finishing university Casinader was employed on TVNZ's Close Up and remained on staff when the programme rebooted as Seven Sharp.
[1] In 2016 Jehan moved to TVNZ’s current affairs programme, Sunday Casinader produced and presented the talk show The Inside Word in 2018 which aired on TVNZ’s Duke channel, tackling tough topics such as negative body image, alcoholism and cyberbullying.