A taste for detective stories always seems to require self-justification on the part of its devotees, against the implication that it exposes either a frivolous mind given over merely to escapist entertainment or a certain blood-thirstiness. Perhaps no branch of literature has called forth so much argument as to whether it is legitimate even to read such things at all. Chesterton thought the detective genre was popular because “serious” literature had departed from ageless perceptions of reality which every person shares at some deep level. It was, he believed, “...the earliest and only form of popular literature in which is expressed some sense of the poetry of modern life.”

His imagination was, as always, gripped by the drama of a romanticized chivalry, and he saw the detective moving across London like “a prince in a tale of elfland,” every lamp post, every crooked street, announcing hidden meanings of which the casual observer is ignorant but the detective is determined to ferret out. The city is actually more romantic than the country precisely because it is man-made. Every urban object, every brick in every wall, signifies something put there by the human mind, waiting to be discovered. “A rude popular literature of the romantic possibilities of the modern city was bound to arise. It has arisen in the popular detective stories as rough and refreshing as the ballads of Robin Hood.”

When Chesterton wrote his essay the stories of Sherlock Holmes dominated the field, and they do not quite seem to fit the description of “rough and refreshing.” This was long before Chesterton first ventured to write his own Father Brown stories. The latter belong to what aficionados of the genre call the Golden Age, an era roughly between the world wars, which managed in a few cases (Agatha Christie) to survive for as long as another half century. But in America, Dashiell Hammett, the writer about whom Raymond Chandler made the famous remark that “he gave murder back to the kind of people who actually commit it,” was already well established at the time of Chesterton’s death.

Haycraft thought Chesterton’s detective stories constituted a third version of the genre, somewhere between the “heavy-handed romanticism” of some Golden Age authors and “the new scientificism.” (The former group presumably include Christie, S.S. Van Dyne, and Mary Roberts Rinehart, the latter encompassing Arthur Conan Doyle, R. Austin Freeman, and Ernest Bramagh.)

But in terms of Haycraft’s duality, the Father Brown stories belong decidedly on the romantic side, which was Chesterton’s explicit rationale for their existence. They could almost be called “gothic” (a term their author would certainly not have resented) in that frequently the characters are menaced by sinister, seemingly supernatural forces which in the end prove to be rationally explicable. Like Doyle, Chester ton was a believer in the supernatural who used his literary talents to disprove supernatural occurrences.

Haycraft criticized some of the Father Brown stories as having solutions which are if anything even less believable than the supernatural itself, a criticism made in somewhat different form by Msgr. Ronald Knox, also a detective-story writer, who thought that, in drawing the reader’s attention to supposedly supernatural occurrences, the Father Brown stories failed in one of the genre’s basic requirements of fastening suspicion on innocent people.

Chesterton often insisted that modern popular rationalism is in fact unrealistic, illustrating the point on one occasion by pointing out the coincidence that “a man named Williams actually does murder a man called Williamson, thus making it appear as though a father has killed his offspring.” It was probably a reference to the Ratcliffe Highway murders in London in 1811, when a sailor named John Williams was accused of murdering two entire families, one of them named Williamson (a story grippingly told by P.D. James, herself a detective-story writer of great distinction, and T.A. Critchley in their book The Maul and the Pear Tree).

At the time of Chesterton’s death Agatha Christie’s immortal Miss Marple had begun her career, and both authors made the same claim about the art of detection — that seemingly ordinary, rather meek, sheltered individuals could unmask great evil simply through their shrewd knowledge of everyday life — Miss Marple her village of St. Mary Mead, Father Brown his confessional and his study.

Golden Age stories have often been criticized as implausible, involving as they usually do sophisticated and wealthy people, house parties on estates, and convoluted plots and counter-plots. But they do in fact reflect a certain kind of reality — connoisseurs of actual crimes can cite such events as the murder of the Hollywood director William Desmond Taylor, for example, or the Madame Fahmy case in London, incidents as “unrealistic” as anything a fiction-writer might concoct. But crimes as strange as many of those Father Brown unravels almost never happen. (Among detective-story writers John Dickson Carr was even more adept at inventing improbable plots, and he allegedly used Chesterton as the model for his detective Gideon Fell.)

For works frankly intended as entertainment, such criticism is of no consequence. But Chesterton did intend his detective stories to provide insight into the nature of evil, and often it appears to be, in his own word, a kind of “elfland” evil unknown to most people.

The definitive study of religious belief and the detective story has yet to be written, but it is probably not a coincidence that some of the leading practitioners of the genre — Chesterton, Dorothy Sayers, Christie, Knox, and others — have been believers. Perhaps the deepest insight into the connection comes from another believer, W.H. Auden, in his classic essay “The Guilty Vicarage,” where he analyzes the genre as a state of tension between an innocent society in no need of law and events which cause it to lose its innocence and thus to be in need of getting set right again by an agent of the law. Father Brown, Auden pointed out, is unique as a detective in being able to offer compassion and forgiveness as well as apprehension and punishment.

Chandler could be accused of reverse snobbery, in that glamorous socialites, suave playboys, domineering tycoons, even clergy and professors, do sometimes commit murder. But the “hard-boiled” school given distinction by Hammett and himself finally does deal with a world which is more “real,” at least in being more statistically probable, than any other school of detective stories. By contrast, glamorous evil, as unmasked by Philo Vance, for example, or metaphysically complex evil, as revealed by Father Brown, appeal precisely to the reader’s fascination with the unfamiliar and improbable. No one expects actually to meet such situations, whereas certain post-Chesterton genres, such as the “police procedural,” address the realistic fears of all modern people.

In his classic essay Chesterton saw the detective as a “knight errant” charged with protecting the “romantic rebellion” which is civilization against the primeval chaos which always threatens it, the detective story’s task to remind the reader of the “knives and fists of a thieves’ kitchen.”

But if Edgar Allen Poe’s Auguste Dupin, Sherlock Holmes, and Father Brown himself might in certain flickering lights be taken for knights errant, that was scarcely to be said of Charles Dickens’ Inspector Bucket or Wilkie Collins’ Sergeant Cuffe, even less of their real-life models, Inspectors Field and Whicher of Scotland Yard. Victims of actual crimes would be well-advised to call Philip Marlowe before contacting Lord Peter Wimsey, and this advice is not merely practical. It also says something about the various authors’ understanding of evil.

Chesterton lamented that the detective story was, with the exception of Robert Louis Stevenson’s work, the only modern literature which explored the fascinating but sinister aspects of the modern city. Oddly, he omitted Poe, the “serious” writer who is credited with inventing the very genre Chesterton was extolling.

Famously, Chesterton illustrated the ubiquity of good and evil by having the great criminal Flambeau become a detective, even as the great detective Valentin was making the reverse pilgrimage. But the history of the police, in all times and places, provides many stories of treacherous moral ambiguity far more chastening and enlightening than the minuet executed between Flambeau and his former pursuer. It was left to the “hard-boiled” school to fictionalize these ambiguities and, if perhaps none of those later writers have been religious believers, and if often they see no grounds for redemption, it is nonetheless true that their fascination with the interplay between good and evil in each soul confirms the Christian understanding of moral reality. (Among Msgr. Knox’s rules for the detective story is that the detective himself must never be the criminal; in reality many have been.)

Thus Chesterton’s pioneer attempt to validate the detective story as a genre did not find complete justification in his own later work and that of his contemporaries. Unpleasant though their stories often are, the “hard-boiled” school is much more effective in reminding the reader of the fragility of civilized life, how thin the barricades which stand between civilization and chaos. Paradoxical though it seems, ex cept for Graham Greene this has not been the achievement of Christian writers of detective stories, even though in principle they seem the best equipped of all to perform it. The Father Brown stories will be read as long as detective fiction itself is read, perhaps not for the reasons their author proposed but as excursions into the unfamiliar universe of moral and metaphysical allegory.