Wholesale Iron River by Daniel Acosta

It's 1958, and a river runs through 12-year-old Manny's life--the railroad that passes along his barrio in San Gabriel, just ten miles east of L.A. It used to be a playground where he could while away time with his friends, throwing rocks at passing trains. Until they find the body of a man they might've accidentally killed with their games. The crooked cop they confess to is just glad to have something to hold against them. He's always been happy to terrorize the whole neighborhood for not being white. So now Manny is tormented by a guilty conscience, and the certainty that police will bang on his front door any day. His family is already struggling with the return of Uncle Rudy, a war-worn man just out from jail. Manny's dad keeps warning him to stay away from Rudy, that he's trouble, but he might have already screwed up his life all on his own.