Among The Dead, Ada Alex Greco Series Book 1

For a helpless, autistic child, it was inevitable. For the prime suspect, a choice. For ADA Alex Greco, a calling. When a beautiful and profoundly autistic boy named Hector is found hideously throat-cut in a Bronx row house, it's his father, a callous and deceitful widower with gang ties, who emerges as the prime suspect.