I don't imagine it would have helped protect Jo Yeates, even if her LL is found to be guilty, but it has made me think about the powerful position private landlords are in. There are too many stories, on here and elsewhere of them abusing that. Prospective tenants have to provide references, but landlords provide nothing, and they keep a set of keys.
My current landlord has threatened to have my neighbours killed. A previous landlord (who lived in the same building as me) once let himself in to my flat when he knew I was in there alone.