The short answer is: it’s complicated.
The slightly longer answer involves the difference between “queer” and “homosexual.”
Actually, you know what? Let’s talk about that. I think it’s worthwhile.
So, briefly: I think that Sherlock and John are a canonical queer couple. I feel that has been demonstrated as unequivocally as it’s possible to do without them actually making out or something.
They have not, thus far (as I think we’ve all noticed), been demonstrated as an unequivocally homosexual couple.
But queer does not necessarily equate to homosexual.
Ceasing to be brief (Jesus, I should install a read-more in this thing): My canonical read on them at this moment—the thing that feels actually true to me, what I see in the show and think that I can reliably argue and support with evidence as outright being there—is that Sherlock and John are in a committed asexual relationship.
Not just a friendship, although it can be hard to explain to people who haven’t had one what the difference can be. An actual committed asexual relationship.
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I think that John is heterosexual (he could be bisexual, but we don’t have concrete evidence for that), and homo…something. Homoromantic? Furthermore, I don’t think this is a new concept for him. I think he knows about it, and possibly even seeks it out.
Before Sherlock, I think he had a previous relationship of this sort with Major Sholto (James). And if we return alllll the way back to ASiP, I think we saw John actively and maybe even consciously on the prowl at their first dinner together for this man he could feel a similar spark with.
I don’t know what Sherlock’s sexual orientation is. I think it’s odd and complicated; I seem to have an instinctual read on him as some sort of demisexual. He was clearly attracted in some way to Moriarty and Irene (though we can’t tell for sure whether there was a sexual component). But I think we can say with confidence by the end of S3 that he fully returns John’s feelings and is a full and aware participant in their relationship.
And I think Mary also sees their relationship and recognizes it, and respects it as being equal though different to her own relationship with John. I think, in fact, that Mary realizes that if she attempted to intervene in or disrupt Sherlock and John’s relationship, she would be jeopardizing her own relationship with John (not to mention risking making an enemy of Sherlock). I think she’s a complicated person who can have multiple motivations for things, but I am pretty sure this is one of her reasons for tolerating Sherlock so broadly.
We’ve all been over the evidence in S3. All three of them speaking in ways that phrase Sherlock and John’s relationship as equal to Mary and John’s—even at the wedding. Sherlock essentially giving a wedding vow. The ‘all three dancing’ line. Sherlock’s jealousy of the way John behaves with Sholto. John’s jealousy (almost squeamish repulsion) of the way Sherlock behaves with Janine. Everything from the prior two seasons—the looks and negotiations and defenses and jealousies and quips.
And when I try to differentiate friendship and a committed asexual relationship…let me see if I can illustrate. First, the level of commitment we’re talking—a lifelong, marriage-style ‘melding our futures and making choices based on the assumption that you will still be here’ kind of commitment.
I think this commitment was there prior to season 3. I think it’s one of the reasons John felt so hurt and abandoned. Many of us observed in S2 how John seemed to have stopped dating, and his jealousy toward Irene, and the very personal way he reacted to things affecting Sherlock. Because I think John was thinking of them as committed.
And I think that when Sherlock showed up and revealed that he’d faked his death, the previous two years took on a new context for John: that of abandonment, not all that far off from a spouse simply up and leaving. When people talk about Mary ‘replacing’ Sherlock—heck, when Mrs. Hudson does—I think it’s spot-on. John moved on. Found a new serious relationship. But he’d never gotten over Sherlock—as you don’t necessarily exactly ‘get over’ a spouse when you are widowed. So when Sherlock came back…now he had both of them. Thankfully Mary wasn’t of a mind to make it awkward.
And this is why Sherlock had to swear his vow. Because he was the one with a responsibility to re-establish the commitment they’d had before.
And again on asexual relationships: there is also the frisson between them. The chemistry. It’s absolutely not friendship. We all have friends, even best friends, but anytime you feel a spark with a friend like the one we see between Sherlock and John, you know there’s something else at work. It’s not just platonic. It may or may not be sexual, but it’s some kind of attraction powerful enough and equivalent enough to be read as sexual very easily.
When I talk about John/Mary/Sherlock threesomes, there is an extent to which I’m not joking. I don’t think that Sherlock and Mary have…something more between them (though they seem to feel and respond to some very interesting parallels and reflections between them). John is the one who serves as the connector. So not a triangle, but still a threesome. And again, the only vow we see at the wedding being Sherlock’s. Him playing for them during their wedding dance. The entire ‘dance’ of the three of them at 221b when the truth finally comes out about Mary—the way the three of them move and reconfigure and finally settle into the classic configuration of Sherlock and John in their chairs. Sherlock is always there. When John’s wedding falters, his relationship with Sherlock is John’s anchor. They can both serve as his tether.
So yes, I think Sherlock/John are a canonical—and established—queer couple. To this extent, I don’t need to believe in the johnlock conspiracy, because I think it’s obsolete. I think they’re already there.
A homosexual relationship, on the other hand… That is definitely not established, and this is the part where I remain skeptical whether it ever will be.
I absolutely think it’s possible, from a characterization point of view, assuming the actors and writers wish to lean that way. John is at least bi-something (maybe not sexual), and Sherlock’s attractions, whatever form they take, seem to have no relationship to the sex or gender of the person he’s attracted to. And they have, always, that searingly powerful attraction between them. Even for a man who normally isn’t sexually oriented toward other men, an attraction that strong could be enough to power an encounter.
Moving on from my own opinions, though, what I find interesting is that when you reach this crux, fans have a lot of different responses.
Some people feel that leaving it at ‘committed asexual relationship’ would be cheating, in a societal sense. As somebody who falls somewhere on the asexual spectrum myself, that’s a bit disappointing in one way, but totally understandable and something I can even get behind in another. I’m sure it’s not the only reason, but part of it is the desire for it to be inarguable. If they’re in an asexual relationship, the majority of society will just keep right on assuming it’s all a straight “bromance.”
There seem to be others who feel like it wouldn’t be ‘real’ if they weren’t also having a sexual relationship. It seems that many people, while they can intellectually grasp the concept of asexuality, can’t really engage with it emotionally. It simply feels incomplete to them. Which makes a certain amount of sense. It doesn’t really quite fit in the patterns we use to discuss love and sex, so it’s hard to wrap the mind around unless you’ve epxerienced it. And sexual people can experience it. Just because you can have sexual relationships doesn’t mean you can’t have asexual ones.
And on that note, some people feel it would be cheating to not leave it at ‘asexual relationship.’ Because admittedly, asexuality gets even less media representation than homosexuality. But then again, it’s a very subtle thing, in some ways. A very internal thing, not easy to render in a visual medium.
And then of course there are the people who prefer that canon be left more or less blank, and that all this stuff remain in the realm of fanworks. For various reasons, which can include having a preference for options not being eliminated, or feeling that if it was made canonical, it’d inevitably just get fucked up, or being sick of main characters inevitably getting hooked up in general…
I’m not really going anywhere specific with this, except to note that Johnlock and queer representation in the media is a more complicated case than yes/no. And maybe to note that shipping and sex aren’t necessarily synonymous, and that at some point in the future, there are conversations pending—not necessarily in the Sherlock fandom, but who knows?—about sexual relations being the default assumption for romantic/passionate relationships.
But anyway, that is my answer. I think they have already consummated a canonical queer relationship. I am doubtful they’ll ever do so sexually in canon.