Against the Evidence — Dell Shannon

To the California police the murder of Lilian Blake seems an open-and-shut case. In less than twenty-four hours they have arrested and charged Harry Nielsen, a mentally disabled youth. At first only Harry's mother believes his innocence, insisting he is too kind-hearted to kill anything. She begs Jesse Falkenstein to accept the case, which he does reluctantly, sure the police have the right man.

But as Jesse starts to dig around, curious scraps of evidence begin to accumulate. He formulates an alternate theory of the crime, and his conclusions expose both Jesse and his wife to a situation of extreme danger . . .

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