Crime in London has become a source of some fascination for many right-wing and Islamophobic observers ever since Sadiq Khan, a former Labour party Member of Parliament and human rights lawyer who is also a Muslim of Pakistani descent, was elected mayor in 2016.
In coverage which reflects negatively on the UK's capital city, right-wing web sites such as Breitbart have taken to referring to it almost exclusively as "Sadiq Khan's London" (a formulation the same sites did not use while Khan's predecessor, the white, Conservative party mayor Boris Johnson was in office). Similarly, in January 2018, anti-Islam blog JihadWatch.com prefaced an article about an increase in crime in the city with "London under its Muslim mayor."
The putative link between Islam and London's violent crime rate (which has in fact been rising, along with that of England and Wales as a whole) is a common theme of right-leaning web sites and blogs. In that vein, the right-wing "Minutemen Militia" Facebook page posted a meme in April 2018 which asserted that "Muslim immigrants" were responsible for the vast majority of "knife attacks" taking place in London the preceding year:
We found no evidence to support the notion that the vast majority of such crimes were committed by Muslim immigrants.
Although the meme did not cite any sources, it is likely the figure of 13,000 knife attacks was taken from January and February 2018 news reports surrounding the UK Office for National Statistics' (ONS) release of a statistical bulletin on crime in England and Wales in the 12 months leading up to 30 September 2017. (The next quarterly report was published on 26 April 2018, two weeks after the meme was posted, so the 13,000 figure could not have derived from that.)
Of that ONS bulletin, the London Evening Standard reported:
Tables giving the precise figures show that there were 12,980 knife crimes in London over the 12 months to the end of last September. That was 2,452 more than the equivalent year earlier.
This figure was subsequently repeated in the Sun newspaper. In fact, the figure of 12,980 knife offenses was taken from separate data published by the UK Home Office (roughly equivalent to the Department of Justice) for crimes involving a knife recorded by the City of London police and the Metropolitan police between 1 October 2016 and 30 September 2017.
A spokesperson for the ONS told us that 12,980 was an accurate figure at the time of the January 2018 news reports, but that in the ensuing months the figures had been revised and updated. As of May 2018, the total number of recorded knife crimes in London, in the year leading up to September 2017, was 13,735.
Figures from local government bear this out. On their "weapon-enabled crime dashboard," the Mayor of London's Office for Policing and Crime stated that 13,767 knife crime offenses took place in the year leading up to the end of September 2017. Some 5,410 of these crimes (39 percent) were knife possession offenses, which are not at all synonymous with knife attacks, as the Minutemen Militia meme apparently categorized them.
We turned up no available figures on the proportion of knife crimes in 2017 perpetrated by Muslims, or by immigrants, or by Muslim immigrants. Neither the Office for National Statistics, nor the Home Office, nor the Mayor's Office for Policing and Crime, has published any such data, so it is entirely unclear what the source of the "11,000" figure claimed in the meme is. (As far as we can tell, law enforcement agencies in the UK do not routinely track the religious affiliation of persons arrested on suspicion of criminal offenses.)
The Home Office does track the ethnicity of criminal defendants and publishes this data once every two years. The most recent report, in 2016, showed that of the 25,121 people convicted for a violent crime that year, 83 percent identified as white, 7 percent identified as black; and 5.8 percent identified as Asian. (A spreadsheet with this data can be downloaded here.)
In the UK, "Asian" is typically used to describe people of South Asian descent (e.g., Pakistani, Indian, Sri Lankan, Bangladeshi) unlike in the United States, where "Asian" is more often used to describe people of East Asian descent (e.g., Chinese, Japanese, Korean). However, nowhere is "Muslim" recognized as an ethnicity, as it is a religion and as such, can be represented by anyone from any country, so it is even more difficult to pin down exactly where their numbers came from.
In 2013, London School of Economics professor Brian Bell conducted a major study of links between the concentration of various categories of immigrants in a region, and rates of crime in that area. He concluded, "The foreign-born share of the population is unrelated to violent crime according to the most recent research findings."