The much publicised report on gangs from the Centre for Social Justice was published at the end of last month, with headlines focussing on the criticism that gang violence had increased since the August 2011 disturbances. (See full report here).
In stark contrast to the claims made about a surge in violence, information on knife and gun injuries sustained (which were reported to and recorded by police) show a significant decrease which began just before the riots (see image below, for full data download click here).
Furthermore, the London Ambulance Service have recorded declines in the number of patients visited/attended to with gun and knife injuries (click here for borough level data and click here for ward level data).
Whilst we know that under-reporting of violence is prevalent, there is certainly a downward trend where recorded data is concerned (from multiple sources), which contrasts the individual opinions of those interviewed as part of the Centre for Social Justice report.
Caution should be exercised with both the data and the report, each harbours its own limitations and methodological errors.