Misled from the beginning until it was fixated in their brains,in other words,brainwashed to believe that Jeremy carried out the murders.
EP had to justify their work in the force because they were already being held over a barrel with the Diane Jones murder prior to this one,,where the police failed miserably in their investigations to find her killer. That case was re-opened this year,but they're probably no further on.
Officers jobs were on the line over this murder,and so as the years have gone by,most will have retired anyway and been secure in knowing that their pensions were intact.
On Mikes' thread,Jeremy was under surveillance,so the police knew where he was on the night of the murders. At home,,and that was midnight,,the time when he was supposed to have committed the murders.