[a cellmate] told prosecutors Williams confessed to the killing and offered details about it.

This is something I found out about recently. They plant an informant as a new cellmate of the person they want a confession from, and give that informant information that only the accused (and law enforcement, of course) would know about the crime, supposedly so that it can be used to wheedle more information. But, when it comes time to tell all, they somehow have all this corroborating information that makes the target look more guilty. How did that happen? /s

Why does the informant do this? Well, they’re in prison too. Any deal they can get is a good deal. And it should make us wonder about the veracity of anything a prison snitch says.

Note that this says nothing about the target’s actual guilt. They might have done it. This is just a technique used by law enforcement to bolster an otherwise shaky case.

And I’m not even saying a plant is what’s happened here. We should still be wary of things said by the prison snitch.