Jabez Wilson had to be created to fit the role he plays in "The Red-Headed League." Sir Arthur Conan Doyle gives him exactly the characteristics he needs. Obviously he has to have a full head of exceptionally brilliant red hair. He had to be something of a tightwad, because he jumps at the chance to earn extra money by copying articles out of the Encyclopedia Britannica, and for other reasons as well. He employs the man who calls himself Vincent Spaulding because he can get his services for half the usual wages. Then when he finds out that the Red-Headed League has been dissolved, he comes to Sherlock Holmes hoping to get free advice and perhaps even hoping that the great detective will somehow get him his cushy sinecure back. But the word that best seems to describe Wilson is "naive."
Wilson never shows suspicion of the Red-Headed League, never shows suspicion of the man who offers to work for half wages, and never shows suspicion of this Spaulding's behavior.
"Never was such a fellow for photography. Snapping away with a camera when he ought to be improving his mind, and then diving down into the cellar like a rabbit into its hole to develop his pictures. That is his main fault, but on the whole he's a good worker. There's no vice in him."
Wilson lets his clerk work at burrowing a tunnel right under his very nose. He never goes downstairs to take a look at what the man is doing. Sherlock Holmes immediately notices "how worn, wrinkled, and stained" the clerk's trousers were, but Wilson never did. At the end of the story Holmes tells Watson:
"...it was perfectly obvious from the first that the only possible object of this rather fantastic business of the advertisement of the League, and the copying of the 'Encyclopaedia," must be to get this not over-bright pawnbroker out of the way for a number of hours every day."
Both Holmes and Watson see from the beginning that Wilson is "not over-bright." They both find him extremely amusing.
"The Red-Leaded League" is one of Arthur Conan Doyle's best stories. He does an excellent job of making the whole fantastic scheme plausible. Jabez Wilson's character is essential to creating the verisimilitude. He has to be someone who is easy to manipulate by a clever man like John Clay. Jabez Wilson makes a very interesting character because of his blazing red hair, his comical behavior, and his childlike simplicity. The best single word to describe Wilson is "naive."