The Dark Page — Samuel Michael Fuller

Carl Chapman has forced life to give him what he wanted, the editorship of the New York Comet, the house with blue shutters, Rose and the children. And now, in a single moment, with two whispered words, it all threatened to come crashing about his ears,
There is no mystery, for the reader, about what happened after that. Carl Chapman murdered the woman who had whispered ... And Lance McCleary, Carl's star crime reporter, saw a story where no one else did, and set out to track the murderer down. Carl had no choice, in self-protection, but to encourage Lance and watch the Comet's circulation boom.

Rich in background color (particularly in its scenes in the Bowery) here is a murder story which depends for its very real suspense not on hidden elements, but on the eventual outcome of the battle between Carl the editor and Carl the man.