[gnicholas]

You're right that a court might find you to be expressing an opinion if you call someone a fraud, but you'll spend a lot of money on your legal defense to find this out. Calling a deep-pocketed person a fraud is buying an expensive lawsuit.

Also, the more memorable mnemonic (at least IMO) is "slander is spoken, libel is not".

[ithkuil]

The quote is: "Slander is spoken. In print, it's libel"

[gnicholas]

You seem to be quoting Spider-Man (if my quick google search is on point); I was quoting my law school professor.

Is Spider-Man well-known as the source of this mnemonic? I’m pretty sure lawyers were saying it for decades before the books/movies came out, but I could be wrong.

[ithkuil]

Well, memes tend to plant in our collective heads, so I guess yes?

Chances are that more people have seen spider man than met your law professor, but yes I'm not arguing that your law professor is a more authoritative source of law related stuff, just saying that I did remember the quote I quoted, for what is worth.

[dr_dshiv]

Spoken slander, literate libel