It's odd that burglary, which was previously the bigger crime problem, is down just as much as violent crime is up:
http://www.crimestatistics.org.uk/output/page7.asp
The thugs stopped nicking anything not nailed down, and instead started stabbing people?
Is this actually a drugs problem in disguise? The US sees increases in murders during times when prohibition is more harshly enforced. When there's more profit in running a drug trade, people pay a higher price in lives.