By an unimportant series of coincidences, I was looking up the origins of the phrase “The butler did it.” The top two relevant results I got were for a trope on tvtropes.com and an article on Mental Floss. The tvtropes article links a Straight Dope on the same subject. All three note that examples of a murder mystery in which the butler was the murderer are rare, but what’s curious is that all three mention a list of rules for murder fiction which SS Van Dine (the pen name of the author who wrote the Philo Vance mysteries) wrote for American Magazine. Though I do have a sneaking suspicion that the two more recent ones may be based on the Straight Dope answer, it is odd that all three cite these rules of detective fiction as if they are authoritative either to what makes a good detective story or to what common tastes were.
Murder Mysteries have been popular for more than a hundred years now, and the idea that there are rules that everyone follows, or that all fans of the genre follows, is absurd. There have been commonalities to detective fiction, to be sure. Giving the readers enough clues to figure out who did it is very common, and very popular, but by no means universal among enjoyable detective fiction. Paranormal, supernatural, and other sorts of detective fiction have been popular. Solutions which could not possibly have been guessed by the reader can be enjoyable as the gradual revealing of an answer. I don’t tend to go for those myself, but pretending that one author’s preference in the 1920s is somehow normative doesn’t accomplish anything.
Within the context of mysteries which aim to be solvable by the reader, most rules (such as Knox’s 10 commandments) aim to give guidance to mystery writers for thinking about the construction of their mysteries. The rules are not meant in an absolute sense, but rather to give sign posts where extra thought is probably required. If the butler, rather than one of the guests, is the murderer, the writer will need to include him as a character enough that the reader thinks that it’s within the spirit of the story to consider the butler.
Now, some might object that it is snobbish to think that the butler is not a possible suspect because he’s just a servant, and indeed it would be, but all problems come with unstated rules, and solving them relies on knowing what these unstated rules are. Consider the classic illustration for teaching people to think outside of the box: Four dots, arranged like the corners of a square, with the instructions to “connect these four dots using only three straight lines without lifting your pen, ending where you started”. The classic solution is to use three lines forming a right triangle where one side goes through two vertices and the other two sides go through one vertex each. This is supposed to surprise people and teach them to “think outside the box” because the rules never said that the end of the lines have to be on one of the four dots. “Don’t limit yourself!” The self-help guru says cheerfully.
The problem with this conclusion is that these sorts of problems are trivial if we’re not helping the person who stated the problem by figuring out what the rules they didn’t state are. No thought would be involved if I just picked up a paint brush and connected all four lines with one thick line. I could even hold my pen against the paper the whole time. Some versions of this mention to not fold the paper; but I haven’t see any rules against cutting and taping the paper. The rules never specified a euclidean geometry; one could easily draw a square then define a geometry in which there were only three straight lines. One could draw new dots and point out that the rules did specify which four dots were the four it was talking about. I could draw three unconnected lines with a pencil while never lifting a pen. etc.
The people who hold this question up as a major revelation are actually practicing a cheap parlor trick. They are really just asking you to try to read their mind and magically know which implied rule they are suspending without telling you. If you were to draw three straight lines plus one curved line, they would balk, rather than applauding you for your willingness to think outside the box in the way that they wanted you to.
The same problem can apply to the butler as the culprit. It would be too easy to assume that the servants are off limits as suspects simply because they all have the opportunity to commit the murder without being noticed, and since detective fiction so often focuses so heavily on alibis, figuring out who had the opportunity is often a large part of the puzzle. Hence this complaint in the tvtropes article:
The butler is the avatar of the most unlikely suspect that, of course, turns out to be guilty because the author wasn’t creative enough to come up with a better way to surprise the reader.
This is a problem only if the butler is the least likely suspect because no time was spent on the butler. Authors who don’t figure out the mystery ahead of the detective, and so who come to the reveal and then have to solve the puzzle for themselves, as it was written so far in order to come up with the ending can run into this. The butler is a good candidate both because he would be surprising since he wasn’t a real character up to this point, and because the servants all have means and opportunity for murder in a great house. This is cheating according to the rules the author implied; to do a good job making the butler the culprit, the author would have had to include the butler as a character in a way that made it clear he wasn’t off limits.
I suspect that this is primarily a problem in mysteries where the author doesn’t know who the culprit is, because it’s all too easy as the evidence is being discovered and alibis are being produced to have accidentally ruled out all of the actual suspects by the end. If that happens, the author will need to introduce a previous non-character who hasn’t been ruled out simply because the author hadn’t thought of the character as a suspect before. I can’t see how such a story can be well crafted; if the author doesn’t know what’s going on, it seems far too likely the story will be inconsistent and not hang together well, though for any technique there is probably someone who can pull it off decently.
But for an example of art criticism which simply wants there to be rules in order to make the task of art criticism easier, consider this from the Mental Floss article:
While The Door was a hit for Rinehart and her sons, who released it through a publishing house they’d just started up, her pinning the crime on the butler has gone down in history as a serious misstep…That The Door was a commercial success while flaunting a hallmark of what some considered lousy mystery writing made it an easy target for jokes. Stories and books like “What, No Butler?” and The Butler Did It soon turned murderous manservants into shorthand for a cheap ending.
Of course this attempt to invoke normative rules of fiction makes heavy use of the passive voice. “Has gone down in history as a serious misstep,” and “flaunting a hallmark of what some considered lousy mystery writing” buys authority with anonymity. There are indeed things which do not need to be attributed—that people will talk about the weather in default of another topic in common does not need to be established with evidence—but common opinion of literary techniques certainly doesn’t fall into that category.
This attempt to have rules of fiction, or more properly rules of art criticism, is not really about the fiction. It is about the desire for stability and intelligibility by a person not willing to do the work of understanding, or without the courage of owning up to their own prejudices and so attempting to displace those preferences onto everyone else.
Incidentally, I looked up the two works cited. “What, No Butler?” seems to be a short story by Damon Runyon. I can’t find much information about it; according to Wikipedia it was in a book called Runyon on Broadway. It was performed on radio in 1946 and that performance is available on youtube. I don’t know when it was originally published. The story does have humor in it, but to call it satire seems like quite a stretch. Early in the story, the character Broadway (who I believe is a theater critic) says authoritatively upon finding out that a man was murdered that the butler did it. When he’s told that the victim didn’t have a butler, he insists that they have to find the butler, because in every play he sees with a murder in it, the butler did it. No one pays attention and he is dismissed because this is stupid advice. In the end we learn that the murderer was a neighbor of the victim, who heard that the victim was rich and so he broke in to the apartment with a duplicated key and killed the victim when he was caught in the act. When asked why he would stoop to robbery, he explained that he was out of work and wasn’t likely to get it again soon. He had served some of the best families in New York, and couldn’t accept just any old employer, because he was an excellent butler. Very clearly, in context, this was not a criticism of the butler as a culprit, but playing with the audience’s expectations to set up a joke.
In 1957 P.G. Wodehouse published a book called Something Fishy. When Simon & Schuster published it in America they used the title, The Butler Did It. Wikipedia gave this plot summary:
The plot concerns a tontine formed by a group of wealthy men weeks before the 1929 stock market crash, and a butler named Keggs who, having overheard the planning of the scheme, years later decides to try to make money out of his knowledge.
(Tontines are in themselves an interesting read. It’s easy to see why they would show up frequently in older detective literature.)
According to the further description of the plot, Keggs is long retired by the time the book takes place. His being a butler is incidental to the story, so far as I can tell, and doesn’t seem like it can be taken as any sort of criticism of detective fiction where the butler is the murderer. This seems doubly true given that The Butler Did It was not the original title, and was only changed because it would resonate better with Americans.
And now that I mention that, it occurs to me that all of the discussion of butlers, from Rhinehart’s story to the supposed criticism of it is all American. Aside from Poe’s character of Dupin starting the genre of detective fiction, much of the most influential detective fiction is British. Now I wonder whether “the butler did it” is a primarily American phenomenon. In any event it does seem to be a very curious example of a saying without much basis, used at least as often to joke about the saying as even to say anything about detective stories.
If I had to guess, I suspect that it originated with someone who was complaining that detective fiction is very formulaic. If so, it is ironic that they picked to exemplify this putative formula a feature which is extremely uncommon in detective fiction.
Having said that, it occurs to me that this idea could even have originated to mean nearly the opposite. It could have started as a parody of the sort of person who doesn’t know how detective fiction goes, and who leaps to the butler as the obvious suspect because he had the means an opportunity for the murder. It would make a more effective criticism of a naive reader than of murder mysteries. “Pffh. He’s the sort of guy who decides ten pages in that the butler did it!” As it stands, I see no more evidence for any other theory of where the phrase came from.