I don't think they are, no.

I've been a witness in court now for two things in the last few years, the first a road accident where the victim eventually sadly died ( I had some key evidence about the road conditions that were considered material), the second was a racially motivated assault on public transport. On both occasions I had to do all the running with the police and had to chase for a statement to be taken. In the case of the accident I responded to the signs for witnesses and waited several months before I called back; they had no record of all the messages I had left with them. The case eventually went to a coroners court where I was called as a witness. The police officer giving evidence lied under oath about something pretty important. The other witnesses and I all gasped when he opened his mouth and complete hogwash came out.

The same thing happened on the second case, the assault. I saw the whole thing happen as well as the build up. I called the police but everyone had cleared off when they got there. I gave my contact details to the victim. I chased and chased for several months before the police eventually met with me to identify the attackers who I saw almost daily on the train and who were constantly pushing and shoving other people off the trains in a manner similar to the racial incident. The perpetrators were BTW white midde class commuters, the victim a pregnant young black women on her own. After about 4 months of my harassing the police(!) someone came to take a statement. I was summoned to court 6 months later; the whole thing took about a year. Because we had set up an ambush for the guilty party (the police were on the platform in plain clothes and I had to physically point out the attackers on the platform) I had asked for this not to be revealed in court in case of any repercussions. The police having agreed to this then let the cat out of the bag in court. I wasn't pleased especially as I had to see these people almost every day for several months again( no custodial sentence imposed so they went back to work and I often sat opposite them on the way home). Just as well they had learned their lesson really and didn't have mates sitting waiting to ambush me!

I watched the news tonight and the piece about someone trying to discourage witnesses coming forward because of false police assurances about protection etc. Its not a savoury story but I have to say my opinion also is that I would not trust the police to keep me safe in anything major, so I would think twice before giving evidence again . They would say anything to get you to get a result and then drop you in it like the proverbial stone.
I took the action I did as felt obliged to be the good citizen however unfortunately I am also not inclined to jump in and defend people so readily again as it only caused me a lot of personal grief and hassle.

When the police go on TV and give assurances about public protection they are not factoring in the administrative incompetence that is such a fact of life in the force.