Hot Time by W. H. Flint

For fans of The Knick, The Alienist, and The Last Days of Night, an entertaining, atmospheric crime thriller set in the Gilded Age.
New York, August 1896. A "hot wave" has settled on the city with no end in sight, leaving tempers short and the streets littered with dead horses felled by the heat. In this presidential election year, the gulf between rich and poor has political passions flaring, while anti-immigrant sentiment has turned virulent. At Police Headquarters, the gruff, politically ambitious commissioner Theodore Roosevelt has been struggling to reform his notoriously corrupt department. Meanwhile, the yellow press is ready to pounce on the peccadilloes of the Four Hundred, the city's social elite-the better to sell papers with lurid stories and gossip or perhaps profit from a little blackmail on the side. When the body of Town Topics publisher William d'Alton Mann is found at the foot of the Brooklyn Bridge, any number of his ink-spattered victims may have a motive.
Hot Time is an immensely entertaining, deeply researched, and richly textured historical novel set in a period that reflects our own, with cameos by figures ranging from financier J. P. Morgan to muckraking journalist Jacob Riis. Our guides through New York's torrid, bustling streets are Otto "Rafe" Raphael from the Lower East Side, one of the first Jewish officers in the heavily Irish force, who finds as many enemies within the department as outside it; Minnie Kelly, the department's first female stenographer; Theodore Roosevelt himself; and the plucky orphan Dutch, one of the city's thousands of newsboys, who may have seen too much.