When quoting a speaker of another English dialect, should you spell things his way?

I realize (or realise?) I may be splitting hairs here, but I find this question interesting, and I’ve never heard or seen it discussed before.

I was about to post a quote from Rich Hickey outside my cubicle, taken from an interview with him, in which the writer uses the traditional British spelling of realize. Hickey is an American, as am I, so I changed it back to the American spelling.

However, it got me thinking: if Hickey were British, should I spell it his way?

The question then is whether I should do so only if quoting something he wrote, or even if I were quoting something he spoke — and thus something he did not actually spell.

Tangentially: should I think of this as quoting Hickey himself, or quoting the author who quoted him?

My gut instinct is that if you’re quoting something written, then you should maintain whatever spelling the author used, and if something spoken then it’s debatable, and using the spelling of your dialect (or of your audience’s dialect) is probably okay.

But I’d like to know: do any conventions exist on this matter?

We can take a look at BBC News for an example of a quoted American (source):

"I struggled with it myself for a long time, but I came to realise that life is that gift from God," [Mr Mourdock] said.

Now let's look at the New York Times quoting a Briton (source):

“I think what he’s achieved will never be bettered in terms of five consecutive Games,” Hoy said. “You start to realize what it means when you actually break it down and see what you have to do and the number of things that can go wrong.”

Unfortunately, many style guides overlook your exact question, but we can see in practice what news sources do. Short of poring over hundreds or thousands of articles from each outlet, it's hard to tell if they are all consistent, but generally the publisher or author will use the spelling conventions of the publisher's or author's country unless quoting directly from a text.

How do we deal with other aspects of a dialect or accent (e.g. preserving someone's g-droppin', etc.)? The answer is, as per some style guides such as the MLA Handbook:

Obvious typographic errors may be corrected silently (without comment or sic; see 13.59), unless the passage quoted is from an older work or a manuscript source where idiosyncrasies of spelling are generally preserved. If spelling and punctuation are modernized or altered for clarity, readers must be so informed in a note, in a preface, or elsewhere.

Note that this describes "typographic errors". However, the quoted speech you describe is transcribed at some point. If you choose to preserve someone's speech verbatim, then you will wind up capturing typographic and grammatical "errors". Therefore, you could apply this guideline.

When quoting a speaker, if she said, "I ain't got nofin' to cook wif," then I could use [sic] or an alternative. It's often suggested, as in this ELU question that "quiet editing" take place, so you would write "I have nothing to cook with" or "I ain't got nothing to cook with" depending on how you want to portray the speaker.

In short, go with your gut instinct.

In my humble opinion, if you change a written quote, it's not a quote any more.

I think of it this way: There are lots of differences in English dialects besides spelling, like vocabulary and sometimes grammar. Suppose a Briton said, "I took the underground to my barrister's office." I don't think it would be legitimate to quote him as saying, "I took the subway to my lawyer's office." That's just ... not what he said. If you can't change the vocabulary, I think by extension you can't change the spelling either. That's why people put "[sic]" or explanatory notes in quotes: So they can give an accurate quote while at the same time helping the reader to understand what was meant.

If you're quoting spoken words, that's a little trickier. Verbal quotes are often not verbatim: we drop out the "ums", fix obvious grammar errors, etc. I can see an argument either way: If you use the spelling of the speaker's dialect, it could look like an affectation, but if you use the spelling of your own, it could look out of place.

If you're making an indirect qoute, like, "Smythe told me that he took the subway to his lawyer's office", that's different. Now you're not claiming to quote his exact words anymore, but rather you are paraphrasing what he said in your own words. My own words use my own spelling. Also, a fair amount of liberty is allowed in "editing" such a quote.

To begin with, in British English both realize and realise are accepted and understood.

As for the question, I've never heard of a convention other than the one you mention: when you quote something written you maintain the spelling the author has used. If you quote something spoken, you can use the spelling rules you are more familiar with and which your readers will understand better.

To add another semi-official viewpoint, the Chicago Manual of Style FAQ have an entry on this, discouraging tampering with the text you're quoting:

Although it’s common to do this in the main text of a manuscript that has crossed the pond, I wouldn’t do it within quotations, partly out of respect for the original and partly because if I failed to catch every last Britishism, I would render the quotation inconsistent and violate my primary rule of copyediting: First, do no harm. If you decide to change the spellings, you could note somewhere that quotations have been edited for spelling and punctuation. For a list of permissible changes to quotations, please see CMOS 13.7.