TWR,
Thanks for responding to my post for you. Don't know if this helps, but Police Officers do indeed find it really frustrating when they spend loads of time and effort in trying to get offenders brought to justice only to seemingly get knocked back by the very system they think is there to support their efforts.
Let me tell you a brief, true story: I was on duty one night when we were called to a punch up at a club kicking out at about 2am. We drove up and there were various people leaving via a first floor flight of steps and halfway down those steps my attention was immediately drawn to one of the bouncers giving a guy a real going over - the guy was prostrate whilst the bouncer stood over him kicking and punching him.
Trying to cut a long story short, it ended up in Crown Court, this bouncer had been charged with assault. I took the stand and before I had a chance to give my evidence, the Judge addressed the jury, and to the best of my recollection, said to them the following:
"You are not to treat evidence from Police Officers any differently to the other witnesses". We had several prosecution witnesses but all of them, simply because they'd been in the club, had been drinking and at the time, they were obviously under the influence, including the guy who'd been assaulted. I, and the other Officers, was stone cold sober.
We went on to lose that case thanks to the Judge's 'advice' to the jury and the smirking bouncer most definitely got away with it. So you can appreciate that frustration I mentioned?