A decision with the most devastating consequences is made in the hunt for Emma's killer. And what happens to the detectives who challenge the order to let their suspect go?
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My name's Alison Hindl and I commission audio drama and fiction for the BBC.
It's a great privilege because I get to unearth stories people love.
You should see the books and scripts covering my floor from new talent and established writers as well as classics.
The BBC has such a rich history of making great audio drama, we're still the largest producer in the world, and the popularity of podcasts means we can share what we do with even more people.
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BBC sounds music Radio podcasts before we begin, I want to warn you that this episode, like all the others, contains graphic descriptions of sexual violence and some strong language.
Episode ten.
Let him go.
Nothing I could have done that night would have made any difference.
There's nothing I could have done that night.
I don't look at Ian Packron that day and think you're a suspect.
The only person that makes that decision is the SIO.
I can't make that decision.
That's the thing about rank and file, about a rule bound organization with a rigid hierarchy.
The decisions made are almost always by those at the top, decisions which leave little room for questions or interpretation only consequences.
I'm Sam Poling from BBC Scotland.
This is who killed Emma.
Episode ten, let him go.
You know when you start talking to someone and they try and ingratiate their self with you, one of the things they'll do is they'll overuse your name.