Crime: a comparison
The useful Disaster Center has some very simply presented tables of long term trend statistics in areas like US traffic accidents and United States Crime Rates 1960 - 2000. The crime rates, based on the FBI's uniform crime reports, are equivalent to the police recorded crime statistics in the UK. Interestingly, they show that murder has not been this low in the US since 1965. Other crimes are similarly at 30-40 year lows: robbery has not been this low since 1968, burglary since 1966, larceny since 1973 and vehicle theft since 1968. The outliers are the brutal violent crimes of rape, still at its lowest level since 1979 (although given what we know about how rape is reported, the earlier figures are almost certainly far too low), and aggravated assault, which is still historically high, although this is the lowest level since 1986.
As for British crime, both the crime survey and the police recorded crime figures are discussed in detail in the official report (warning -- 199 page PDF).
Anywat, here are my calculations of comparable police recorded crime rates per 100,000 population. They're back of an envelope (literally), but are pretty indicative in my opinion:
Murder: US 5.5, UK 1.67 (US 223% higher)
Rape: US 32.0, UK 66.27 (UK 107% higher)
Robbery: US 144.9, UK 204.11 (UK 41% higher)
Aggravated Assault*: US 323.6, UK 432.93 (UK 34% higher)
Burglary: US 728.4, UK 1657.6 (UK 127% higher)
Larceny: US 2475.3, UK 3658.2 (UK 48% higher)
Vehicle Theft: US 414.2, UK 597 (UK 44% higher)
*This is the area with most discrepancy between the two classification systems. US aggravated assault means "an unlawful attack by one person upon another for the purpose of inflicting severe or aggravated bodily injury". I have interpreted this by including the British offenses of attempted murder, "wounding or other act endangering life", "other wounding" and "racially-aggravated other wounding." I think this is fair, as a lot of aggravated assaults in the US would probably be classed as "threats or conspiracy to murder" in the UK, as no actual bodily harm results. What you gain on the swings you lose on the roundabouts here.
Anyway, this leads us to the crime index totals:
Violent crime US 506.1, UK 705 (UK 39% higher) and
Total crime index US 4124, UK 6617.8 (UK 60% higher).
Pretty conclusive as to which is the safer place. Unless you're a drug dealer, of course...

