Suppose I'm a major newspaper journalist. A rape occurs, and the police arrest the suspect. Bucking all journalistic trends, I run a story with the headline, "Rapist CAUGHT," not "Alleged Rapist Caught."
As time goes on, it is eventually proven that the "rapist" did not actually commit the act, and I or a fellow journalist promptly retract my previous statement.
In the first article, did I commit libel? Does it matter whether or not I had reason to believe what I published was accurate?
What you reasonably believed to be true about the guilt of the rapist is moot; you could argue that you reasonably believed he was guilty, but you'll probably have to admit you didn't have the facts of the case to make a final judgement about guilt. That's what libel is: the stating of provably false facts.
But mostly the problem will be that you didn't know the difference between an arrest and a conviction. People are arrested under suspicion of a crime when there is reason to believe valid evidence exists that they committed the crime, or that the evidence already exists. If it turns out that the evidence doesn't exist, the prosecutor won't prosecute, and the arrested person is released, and their arrest record expunged in some cases.
And, yes, chances are very good the paper will have to print a retraction, due to a lawsuit or insistence of their own legal department. But any news or copy editor is going to add "alleged" to any such "the criminal is caught" headline, because that's one of the jobs of an editor or copy editor: to try and keep the paper from being sued for defamation by the named person who turns out to be innocent. So that libelous headline wording is rarely going to appear in print, anyway.
And if you're only a journalist, you're not going to be writing the headlines; editors and copy editors do that. The separation of the writing of the article and the headline is traditional in journalism, and one of the reasons is above.
If you in fact run your own paper or website and are the reporter and editor, good luck: that you didn't know the difference between an arrest and a conviction is probably the plea you're going to make to the jury or judge when you get sued for defamation and you're really hoping the civil court judgement doesn't financially destroy you.
In the first article, did I commit libel?
It depends on whether the journalist's reasons persuasively justify his emphatic departure from all journalistic trends (as you put it). For the prima facie elements of defamation/libel/slander, see In re Lipsky, 460 S.W.2d 579, 593 (2015) (these elements are largely common to most or all jurisdictions in the U.S.). You will notice that a prima facie case involves "(3)[a] requisite degree of fault", which could be negligence or with actual malice (i.e., defamer's knowledge of the falsehood of his statements).
The journalist's emphasis in "Rapist CAUGHT" reflects his strong interest in impressing on the public a negative image of the defamed person. That use of uppercase and the absence of cautionary terms such as "alleged" tend to heighten the journalist's burden of proof regarding his state of mind.
Lastly, it is important to clarify something about this comment. Although the title "Rapist CAUGHT" in and of itself gives no one what is called standing to sue for defamation, it is wrong to rule out a viable case therefor. Indeed, a scandalous title is very likely to prompt readers to read the article, which might in turn identify the person whose reputation is harmed as a result of the title and/or other contents in that article.
There is no libel in the headline in itself.
Presumably the article identifies an individual and some or all the whole piece has the effect of saying the individual is the rapist.
In the UK since January 2014 'honest opinion' is a defence to a defamation claim. The publisher must show that the statement was a statement of opinion, the statement indicated the basis for the opinion, and an honest person could have held the opinion based on "any fact which existed at the time the statement complained of was published" or "anything asserted to be a fact in a privileged statement published before the statement complained of".
"The ultimate question is how the word would strike the ordinary reasonable reader. The subject matter and context of the words may be an important indicator of whether they are fact or opinion." - Koutsogiannis v The Random House Group Ltd [2019] EWHC 48 (QB)
In the UK in 2011 eight national newspapers settled libel cases for a guesstimated six figures with a man after publishing some 40 articles that gave the false impression he was a kidnapper, murderer, voyeur and paedophile after his arrest in connection with a kidnap and murder investigation. Subsequently a different man was found guilty of that kidnap and murder.
It seems worth noting that two of those newspapers were also found guilty of contempt of court for publishing information that could prejudice a trial. In some jurisdictions it is a contempt to publish anything that creates a substantial risk of serious prejudice or impediment to the course of justice in legal proceedings and the truth or falsity of the statement is irrelevant.
A reasonable person would expect a journalist for a major newspaper (presumably, a national daily or similar) to understand the difference between charge and conviction.
In the first article, did I commit libel? Does it matter whether or not I had reason to believe what I published was accurate?
You didn't commit libel, and your belief does matter. If you knew the person was innocent at the outset you might have liability.
In U.S. Constitutional law, the minimum standard for imposing defamation liability upon a media defendant regarding a matter of public interest, such as whether a criminal at large has been caught, was articulated in the U.S. Supreme Court case New York Times Co. v. Sullivan, 376 U.S. 254 (1964), which remains good law. This requires a showing of either knowledge of falsity, or reckless disregard for the truth. This is a publisher's intent based standard.
Furthermore, a statement is generally not subject to defamation liability if the factual basis for a statement is disclosed, as it generally would be in the body of the news story, and which would generally include a press release or statement from the law enforcement agency that made the arrest. The law permits you to make an overstated headline and then pull your punches with a more balanced body text to support it, so long as you make clear that the basis of your conclusion is the facts that you disclose and you don't imply that you are relying on other undisclosed facts for your conclusion.
The statement made also needs to be interpreted reasonably and not in an unduly literal or hyper-technical manner. In this context, someone familiar with how the criminal justice system in the United States works, would know that "Rapist caught" almost surely, on its face, means that someone suspected of a rape has been arrested, and not that someone has been convicted beyond a reasonable doubt by a jury of that crime. An interpretation that you had direct knowledge that the arrested suspect was guilty would be unreasonable under the circumstances which the headline itself makes clear.
Thus, it is very unlikely that this headline would give rise to defamation liability for the reporter or the firm that published the story, unless you had knowledge that the suspect who was arrested was innocent at the outset.
U.S. defamation law is atypically globally (i.e. it is pro-speech compared to the laws of most other countries), however, and isn't a good guide to the majority rules of defamation law outside the U.S.
You don't state the jurisdiction. Under US law, the standard is different depending on whether the person defamed is a "public figure". If they are, they have to show reckless disregard for the truth, while someone who isn't has to show only negligence. If we take the hypothetical given in your title, that you had a reasonable basis for your belief, without question, then this would be a defense. However, whether you in fact did have a reasonable basis would be a question for the trier of fact. In the body of your question, you just say "had a reason to believe". Merely having some factual basis for a claim, especially for a non-public figure, is not sufficient to defeat a libel claim.
Reporters often take this "alleged" stuff to an absurd extreme, however, such as saying "alleged suspect". If the police identify someone as a suspect, then it's clearly objectively true that they are a suspect. No "alleged" is needed.
