Numbers are difficult to compare since data collection mechanisms are subject to change, but here you go:
https://en.wikipedia.org/wiki/Crime_in_London
The need for CCTV is marketing and gut feeling from my perspective because the numbers say it didn't do much.
Per that article, in 2010 the vast majority of violent crime offenders were black - and I wouldn't be surprised if the victim profile would look similar.
Pure anecdata, but this was 90% of the news I saw. Gang stabbing in park. Gang stabbing at party. Gang shooting at club.
Meaningless without comparison to other countries.
> London is the knife crime capital of the world.
Doubt it. https://en.wikipedia.org/wiki/List_of_cities_by_murder_rate
The statistics were compiled from 2015 and in just the few years since then solved crimes have halved: https://www.bbc.co.uk/news/uk-49029545.
If you and I were to travel back in time to the high trust society before mass surveilance & enquired our police wouldn't deny they held the the monopoly on violence. My friends in the forces of today tell me they feel under siege most days.
Apologies, "London is the knife crime capital of the world." is part of the venacular here akin to "The man who broke the Bank of England".