Utterly untrue- your words, please don't use an old piece of case law to try to back up an argument R-V- Comish ex parte Blackburn, the full case not the wiki version is about failure to prosecute gaming houses in the 60's, whilst it does provide some useful guidelines it's not what you think it is
The police are no longer the prosecuting agency, as was then, its the crown prosecution service
Policing priorities are set by govt through the national policing board, these are then passed down to PCC/Mayors who in turn pass them to their Commissioner/ Chief constable who sets a strategic policing plan.
Crikey even the Home Office decide what and what isn't a crime worthy of investigating through Home Office counting rules.
Every cop I knew and with 31 years in the job I knew a few, wanted to deal with what we knew to be the problems in our own little areas, not some strategic plan formulated by bag carriers based at HQ, but it's a disciplined organization and you do what your told.