The event, marking the 20th-anniversary screening of the film Wag the Dog, took a turn when Oliver alluded to a sexual harassment accusation leveled at Hoffman, given the current climate following the news of the allegations against Harvey Weinstein.
"This is something we’re going to have to talk about because…it’s hanging in the air," the HBO show host told Hoffman.
In a tense exchange – which Hoffman was unprepared for – the pair sparred over Hoffman's response to allegations made by Anna Graham Hunter that he groped her during the filming of the 1985 film Death of a Salesman.
Hoffman, who returned to the topic unprompted according to a Washington Post reporter who was present, had apologized for his behavior after the allegations first emerged, but on the panel questioned whether events as described by Graham Hunter took place.
"I still don’t know who this woman is," Hoffman said, according to a Washington Post report. "I never met her; if I met her, it was in concert with other people."
Hoffman said the allegations were not representative of him as a person, but Oliver responded: "It’s ‘not reflective of who I am.’ It’s that kind of response to this stuff that pisses me off."
The audience watching appeared divided, with many reportedly calling for Oliver to leave the line of questioning and return to discussing the film, while others in the audience seemingly stood up and applauded.
In the hours after the incident, many people on the internet were wholly in Oliver's camp.
Some women zeroed in on one of the most important parts of the exchange:
Although many applauded the host, others did question whether he was right to criticize Hoffman so publicly and unexpectedly. And some people just criticized Oliver for bringing up the subject in the first place.
Many women — and men — tweeted that, whatever the circumstances, Oliver's stance should be celebrated.
Many noted that, accusations aside, it was extraordinary to see such an established figure being asked to account for his actions so publicly.
Others added that, irrespective of Oliver and Hoffman's public status, the host was doing what all men need to be doing right now:
Many felt this summed it all up for them.
BuzzFeed News has contacted representatives for Hoffman and Oliver.