Ever since his “Last Week Tonight” launched on HBO in April of 2014, people have been calling John Oliver names.

They keep insisting he’s a reporter or a journalist. They say he does something called “investigative comedy.” And they believe he sheds important light on topics that often go ignored or misunderstood and yet need to be digested in full – a task often performed by the best non-fiction efforts.

Ever since his “Last Week Tonight” launched on HBO in April of 2014, John Oliver has insisted he’ s not involved in any of those activities. “I wouldn’t say I’m a basketball player because I like basketball,” he told a group of people who call themselves journalists earlier this week. “I am not a journalist. I think that’s factually clear.”

Not to the show’s viewers. In an era of splintering audiences who coalesce around niche media and partisan news outlets, anyone with a miniature camera and a Facebook account can claim to break news and deliver previously untold facts. And while Oliver and many of his late-night contemporaries swear up and down that they are just trying to make people laugh, their intentions these days matter less than the interpretations their audiences make of their work.

Is John Oliver a journalist, despite his protests? “It’s a question you have to answer with another question: What is a journalist in this day and age?” says Geoffrey Baym, author of the 2006 book “From Cronkite to Colbert: The Evolution of Broadcast News” and chair of the Department of Media Studies at Temple University. Oliver “doesn’t get press credentials. He has no access. He’s not in the White House briefing room every day. His agenda is much blurrier. But none of that is to say he’s not really doing important work – discussing public affairs in a really intelligent, fresh way that brings issues to light that people might not know about.”

Oliver’s specialty is seen each Sunday on “Last Week Tonight.” In segments that can last as long as 15 to 20 minutes – sometimes more (and often longer than the typical “60 Minutes” segment) – he guides viewers through the nuances of subjects ranging from gerrymandering to the management of nuclear waste. To be sure, each of the segments – and the shorter ones that support it – are leavened with a healthy dose of humor. Oliver is not above luring a pack of dogs to stand in for the Supreme Court or running clips of local news anchors dressing up on air for Halloween.

Despite the jokes, a soon-to-be published study finds that Oliver’s work sways the opinion of people who watch him. One of the segments that brought Oliver to wider renown was an 11-minute examination of so-called “net neutrality,” or a policy that holds online service providers should offer equal access to all content and applications, no matter their origin. Researchers working with the University of Delaware’s Center for Political Communication found in 2015 that people who watched “Last Week Tonight” were moved more by Oliver’s program to support net neutrality protections than by any other mainstream media source, says Dannagal Young, an associate professor of communications who took part in the analysis.

“Exposure to his show had the strongest impact of all of the news media outlets we asked about,” says Young. “We did not find any effects of exposure to CNN, MSNBC, newspapers – none of those things were related to public opinion on net neutrality.”

Oliver isn’t the only host in TV’s “late night” category whose work might be easily confused for actual fact-finding. Conan O’Brien has been taking interesting trips to places like Bulgaria and South Korea since 2015, when he became the first American TV host in decades to visit Cuba and film there. Earlier this week, Samantha Bee sent a short dispatch to Variety after experiencing a blackout while traveling in Puerto Rico for a one-hour special being prepared for ther TBS show, “Full Frontal.” Seth Meyers’ signature segment on NBC’s “Late Night” these days is his “A Closer Look,” which, if one isn’t careful, might be easily mistaken for a news analysis piece (except that it’s funnier). Bill Maher has acknowledged some of his viewers watch his “Real Time” to catch up on the headlines, prompting him to wonder if they are on the right news regimen: “It’s like saying I get all my nutrients from the Cheesecake Factory,” he said to Variety in 2015. Stephen Colbert regularly nabs guests like Anthony Scaramucci and Billy Bush whose claim to fame is being in the headlines, not necessarily having a new movie to promote.

Ask any of them (this reporter has) whether it’s more important to get people to laugh or to think, and they will tell you the former. “I will say no matter how thoughtful a piece was, if no one laughed I would be devastated,” Meyers told Variety last year. “If anybody who worked at this job felt they were in competition with the news, I think they should probably just go do news,” Colbert said to Variety last year.

There’s one thing the comics can point to that might keep them from being confused with Woodward and Bernstein or Maggie Haberman. Most of the material they use in their routines comes from other sources. Oliver’s program makes use of clips from everything from PBS’ “Frontline” to Al Jazeera. “Without them, we could not do our show, for sure,” Bee told Variety last year about journalists (Indeed, her “Full Frontal” one week celebrated CNN’s Jake Tapper.)

And yet, “Last Week Tonight” and “Full Frontal” have employed researchers with journalism backgrounds. Oliver this week described a process on his program under which staffers check facts with the entities being discussed on his program. These people may not like how they are portrayed on the show, he said, but he hopes they cannot find fault with the procedures used in advance of the segment’s appearance on TV.

The comedians have reason to avoid being labeled reporters – and not just because of the long hours and endless production of paragraphs that is part of a life in the Fourth Estate. “They want to be able to do what they’re doing without being under the same kind of pressures that journalists are,” says Young, the University of Delaware professor. “They want to have the artistic freedom to say what they want to say.”

Much of this may be moot, however. Whatever Oliver and late-night hosts intend, their audiences are picking up something else. They have been for some time, as anyone who can tell you he or she thought Jon Stewart was some modern incarnation of Walter Cronkite can tell you.

“All of this is because we live in a world with infinite sources of media, hundreds of TV channels and infinite websites,” says Baym. “Those old rules about who’s going to speak and what they had to sound like when they did so – those no longer apply.” Comedians like Oliver, he adds, sound a lot like us, and their casual tone often proves more appealing to modern audiences than that of a TV journalist bound by the medium’s traditions.

Oliver’s protests sound a lot like the introduction to Mark Twain’s “The Adventures of Huckleberry Finn,” in which a narrator tells readers: “Persons attempting to find a motive in this narrative will be prosecuted; persons attempting to find a moral in it will be banished; persons attempting to find a plot in it will be shot.”

That book, one of the most seminal works in American literature, does contain a motive, a moral and a plot – just as Oliver’s work serves some journalistic function. In the end, it’s up to the audience. In these days of social-media opinion being taken as the equivalent of hard, cold fact, if some people believe John Oliver’s a journalist, he might as well be one – no matter how regularly he protests.