What's unfortunately 'needed' to bring about any kind of change (IMHO) is the death of someone very high profile, and a resultant media circus that brings the whole sorry excuse for justice into the light.
Re: phone hacking. People were bothered, but the revelations of Millie Dowler's hacked mobile suddenly made the public sit up and think. Before that, it was abstract.
If you read the article on Holland, this is just what it took- a high-profile politician's child being killed, and a resulting campaign to change things.
I'm not nominating anyone, but someone like Leo Blair getting crushed while negotiating a traffic island would do it. I'm not being flippant, this is just the way minds work.