Why We, the Accused, differs from most crime fiction

As I near the end of Ernest Raymond's thoughtful and richly detailed account of a murder and its aftermath, We, the Accused (1935) - in which an otherwise self-effacing 50-year-old private-school teacher in London poisons to death his somewhat older wife so that he can legitimize his affair with a  30-something (though by all accounts not a predatory beauty but a modest and serious young woman) workmate. Sure, this novel could be edited and tightened - Raymond steers away from no detail - and sure it doesn't really rise up to the level of its perhaps inspiration and counterpart, Crime and Punishment, but it's a particularly interesting social document, giving us a great deal of information on the whole process of the British justice system, right through the arrest, imprisonment, trial (and I haven't finished yet but, execution?) which careful character development and scrupulous background, even of the arresting officer and the prosecuting attorney, as well as Dickensian character sketches of most of the other characters, many of whom are merely incidental to the plot. What's particularly of note is that ER brings us through the whole trial scene w/ a feeling of great empathy for the protagonist, Paul Presset, and we expect his exculpation, and want that, even though we know that he's guilty (his paramour learns of this quite late in the game; not sure yet of how she'll be treated by the justice system). Most such novels keep us in doubt about the key facts of the crime, and most involve an innocent man crushed by the impersonal system of justice; not in this case. If you can make it through the needlessly detailed chapters - such as the yard-by-yard account of Presset's run from the law - to the British Coast, then to the Lake District (all of which might do well on film), there's plenty to enjoy in this copious novel, far more detailed and thoughtful than most of its brethren in "crime."