The new film follows a man named Arthur Fleck, whose stability is rocked after he is disregarded by society. Despite Joker generating Oscars buzz and winning festival plaudits, a number of critics have voiced their concerns over some of the film’s more disturbing scenes, which show Fleck's descent into psychosis.
Phoenix was asked by The Telegraph if he thought particular moments in the film "might perversely end up inspiring exactly the kind of people it's about, with potentially tragic results". Instead of answering, the actor walked out.
According to journalist Robbie Collin, as the actor left the room, he asked why he would ask such a question.
Warner Bros employees eventually managed to talk him into returning to complete the interview.
Joker's director Todd Phillips recently revealed that Phoenix would walk off set in the middle of a take if he "wasn't feeling it", worrying his co-stars.
The debate over violence in film has been prevalent in recent months following a series of mass shootings in the US. Last month, Universal pulled the release of new thriller The Hunt, a film following 12 red-state strangers who wake up in a clearing and realise they’re being hunted by liberals.
Joker is released in cinemas on 4 October.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies