There is a series of murders from the 70s and 80s I think could be fictionalized into a great novel. But I hesitate to do so. The killer's motive was interesting but it is recent history that affects real people.
That's exactly what some writers do, though I forget what they call it. I'll call it "nonfiction murder mystery."
But those writers who write nonfiction murder mysteries can offer a good deal of insight to a case, and potentially help solve a crime that had long gone unsolved. I have no examples to pull out of my rear-end, however, so I'll be going now.
I'd never thought of that. I'm not a mystery writer, though what got me thinking about this and actually inspired me was the whole Supreme Court taking out Section 5 of the Voting Rights, which protected the voting rights of minorities. It got my wheels-a-turning.