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Dame Cressida Dick fielded questions about how the police were dealing with the lockdown, and with knife crime and crime generally, with a focus on racial differences, particularly on the numbers of people stopped and searched.
https://committees.parliament.uk/oralevidence/668/pdf/
https://committees.parliament.uk/oralevidence/668/pdf/
"If I go to violent crime, in London last year 72% of homicide victims under 25 were black. Nationally—you probably know the figures—you are four times more likely to be a victim of homicide if you are black and eight times more likely to be a perpetrator."
"The overlap with my key metric, which is knife injuries for under 25s, which we have been reducing for the last two years and into this year, shows enormous disproportionality in the way it affects our young black men as victims and, I am sorry to say, as perpetrators."
"That is horrible. For knife robbery, gangs, county lines, line holders: hugely disproportionate."
The “8 times more likely to be a perpetrator” figure for Black British was not generally known, so it was a surprise to hear it in a public arena. The figure is roughly the same as that for homicide for African Americans, despite their different histories.
US Police and UK Police differ considerably, in that the latter are not usually armed. That does not appear to make a difference in the ratio of black to white offenders.
Black British were originally from the West Indies, and after 70 years in the UK, whatever their experiences, they were not subjected to possibly 500 years of life in the US.
It is either a coincidence that both homicide rates are equally raised, or it suggests that the US experiences are not a unique cause of Black homicide rates.
The relevant results are in Table 27, showing 800 convictions for homicide. (The last three rows of numbers are the population expectations, which I have added in).
Blacks 3.3% of population account for 17.6% of murders, 5.34 times more than expected.
Whites 86% of pop account for 69.8% of murders, 0.81 times expected, so less than their population numbers. Putting the two together means that Blacks are 6.6 times more homicidal than Whites.
Whites 86% of pop account for 69.8% of murders, 0.81 times expected, so less than their population numbers. Putting the two together means that Blacks are 6.6 times more homicidal than Whites.
26 times more Whites than Blacks in England & Wales, but Blacks murder more Whites (45), than Whites murder Blacks (11), a 4-fold difference. Proportional to their numbers, it is far more likely that a Black person murders a White person than the other way round.
The likelihood of a Black person murdering a White person is 45/(56,100,000*.033) = .0000243072
The likelihood of a White person murdering a Black person is 11/(56,100,000*.86) = .000000227998
The likelihood of a White person murdering a Black person is 11/(56,100,000*.86) = .000000227998
What hit rate makes the Stop and Search policy worth-while? According to the figures, 10,000 out of a population of 80,000 black men have been stopped and searched with a hit rate of 20-28%.
A search does not have to be interpreted as a humiliation, but it certainly implies suspicion, and can be a cause of resentment if it happens very often.
However, it also protects even those who are irritated by it.
However, it also protects even those who are irritated by it.
One question to which we don’t have a precise answer, even though it is highly relevant, is what the chance is of finding weapons, drugs or stolen property on an average citizen, or even on an average young Londoner. We can estimate it thus:
1,033,0305 19-24 year-olds in London. 15,590 knife crimes last year. Assume each knife crime is perpetrated by one knife carrier, then 1.5% of young men carrying a knife. If Police stop young men at random, for every 10,000 stopped they will get a positive result in 150 cases.
For every 10,000 Black Londoners, assuming that the 8 times higher rate of offending is correct, they would find 1,200 offenders. In fact, they found 2,000 offenders. The Police did a good job.
They chose well, not only noticed suspicious behaviours, but probably also recognized frequent offenders. Police have noticed some things about criminals.
It is hard to stop people noticing things, unless of course you punish them for it, or pay them not to notice.
It is hard to stop people noticing things, unless of course you punish them for it, or pay them not to notice.
By searching 5 young Blacks you prevent 1 offence, possibly a very serious one. In the process, you might irritate 4. Is it worth it? We are looking at Numbers Needed to Treat, & Numbers Needed to Harm. No medicine cures every single patient, so NNT = 1 is usually a dream.
