Matt Ashby
@mattashby.com
I help people use data to reduce crime. Associate Professor, Crime Science, UCL. Former police officer.
🌐: mattashby.com
🌐: mattashby.com
One absurdity of the 43-force police structure: the investigation of Mandelson is done by the Met because he was probably in London when he emailed Epstein, while the investigation of Andrew is by Thames Valley because he was in probably in Berks when he did the same.
www.bbc.co.uk/news/article...
www.bbc.co.uk/news/article...
Police assessing claims about Andrew sharing confidential trade details
It comes after files suggest the former prince shared confidential information with Jeffrey Epstein from his official work as trade envoy.
www.bbc.co.uk
February 9, 2026 at 3:18 PM
One absurdity of the 43-force police structure: the investigation of Mandelson is done by the Met because he was probably in London when he emailed Epstein, while the investigation of Andrew is by Thames Valley because he was in probably in Berks when he did the same.
www.bbc.co.uk/news/article...
www.bbc.co.uk/news/article...
Very interesting blog post on how the lack of a coherent approach to the police workforce is hurting police productivity (with some especially jaw-dropping numbers on the financial cost of police disciplinary investigations very-often being far too slow).
leapwiseadvisory.com/current-poli...
leapwiseadvisory.com/current-poli...
Current police workforce strategy (or the lack of it) is hurting police productivity - Leapwise
The new Increasing Police Productivity report was published last week, following the Public Accounts Committee’s (PAC) inquiry in November 2025. The PAC
leapwiseadvisory.com
February 9, 2026 at 3:02 PM
Very interesting blog post on how the lack of a coherent approach to the police workforce is hurting police productivity (with some especially jaw-dropping numbers on the financial cost of police disciplinary investigations very-often being far too slow).
leapwiseadvisory.com/current-poli...
leapwiseadvisory.com/current-poli...
One advantage of the wet weather: waterfalls currently look amazing!
📍@nationaltrust.org.uk Aira Force
📍@nationaltrust.org.uk Aira Force
February 7, 2026 at 2:09 PM
One advantage of the wet weather: waterfalls currently look amazing!
📍@nationaltrust.org.uk Aira Force
📍@nationaltrust.org.uk Aira Force
Reposted by Matt Ashby
If you can spare 2 minutes for a survey on street lighting and perceptions of safety, I have a student who would be very grateful! 👍
qualtrics.ucl.ac.uk/jfe/form/SV_...
qualtrics.ucl.ac.uk/jfe/form/SV_...
Qualtrics Survey | Qualtrics Experience Management
The most powerful, simple and trusted way to gather experience data. Start your journey to experience management and try a free account today.
qualtrics.ucl.ac.uk
February 4, 2026 at 6:59 PM
If you can spare 2 minutes for a survey on street lighting and perceptions of safety, I have a student who would be very grateful! 👍
qualtrics.ucl.ac.uk/jfe/form/SV_...
qualtrics.ucl.ac.uk/jfe/form/SV_...
If you can spare 2 minutes for a survey on street lighting and perceptions of safety, I have a student who would be very grateful! 👍
qualtrics.ucl.ac.uk/jfe/form/SV_...
qualtrics.ucl.ac.uk/jfe/form/SV_...
Qualtrics Survey | Qualtrics Experience Management
The most powerful, simple and trusted way to gather experience data. Start your journey to experience management and try a free account today.
qualtrics.ucl.ac.uk
February 4, 2026 at 6:59 PM
If you can spare 2 minutes for a survey on street lighting and perceptions of safety, I have a student who would be very grateful! 👍
qualtrics.ucl.ac.uk/jfe/form/SV_...
qualtrics.ucl.ac.uk/jfe/form/SV_...
Homicide is often made more likely by 'enhancers' such as drugs, alcohol, mental health or the involvement of street gangs. This thread summarises what we know about factors that make homicide more likely.
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February 3, 2026 at 3:00 PM
Homicide is often made more likely by 'enhancers' such as drugs, alcohol, mental health or the involvement of street gangs. This thread summarises what we know about factors that make homicide more likely.
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The most-common victim of homicide a young man killed during a brawl. But what about child homicide, elder abuse and domestic abuse? This thread summarises what we know about homicide vulnerability for those specific groups in society.
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February 2, 2026 at 3:00 PM
The most-common victim of homicide a young man killed during a brawl. But what about child homicide, elder abuse and domestic abuse? This thread summarises what we know about homicide vulnerability for those specific groups in society.
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Reposted by Matt Ashby
Law is not magic, and prohibitions are not spells.
All a prohibition does is to change the legal and other consequences when a prohibited thing happens.
Some prohibitions make sense, others make no sense at all.
All a prohibition does is to change the legal and other consequences when a prohibited thing happens.
Some prohibitions make sense, others make no sense at all.
Drug laws have never stopped people from using drugs.
They've stopped people from using drugs safely.
It's time to legalise *and* regulate.
www.bbc.co.uk/news/article...
They've stopped people from using drugs safely.
It's time to legalise *and* regulate.
www.bbc.co.uk/news/article...
Drugs policy approach needs to change, Zack Polanski says
The Green Party leader of England and Wales says there needs to be a
www.bbc.co.uk
February 2, 2026 at 12:14 PM
Law is not magic, and prohibitions are not spells.
All a prohibition does is to change the legal and other consequences when a prohibited thing happens.
Some prohibitions make sense, others make no sense at all.
All a prohibition does is to change the legal and other consequences when a prohibited thing happens.
Some prohibitions make sense, others make no sense at all.
Reposted by Matt Ashby
Just bizarre to me that there is such a large market for "AI will go away on its own" at this stage. And that so few people who serve that market seem to have updated their beliefs at all in the past year, even as key tasks like coding have already started to change beyond recognition.
February 2, 2026 at 3:30 AM
Just bizarre to me that there is such a large market for "AI will go away on its own" at this stage. And that so few people who serve that market seem to have updated their beliefs at all in the past year, even as key tasks like coding have already started to change beyond recognition.
Reposted by Matt Ashby
The weirdest conspiracy theory of all is that 15 minute city thing. Why would anyone not want 15 minute cities? I mean you can still live in the countryside if you want but all villages, towns and cities should have amenities within 15 mins.
February 1, 2026 at 11:56 AM
The weirdest conspiracy theory of all is that 15 minute city thing. Why would anyone not want 15 minute cities? I mean you can still live in the countryside if you want but all villages, towns and cities should have amenities within 15 mins.
Are any forces doing this? It sounds like a useful bit of strategic analysis.
Does anyone know of any examples looking at what % of total police recorded crime harm is brought to justice as a weighted measure of police performance?
I'll give that some thought - so e.g. what % of total police recorded crime harm is brought to justice?
Incidentally, see the rest of the thread. Humberside is interesting for having a v high shoplifting charge rate, but being weaker in higher harm areas, notably rape.
Incidentally, see the rest of the thread. Humberside is interesting for having a v high shoplifting charge rate, but being weaker in higher harm areas, notably rape.
January 31, 2026 at 6:21 PM
Are any forces doing this? It sounds like a useful bit of strategic analysis.
Reposted by Matt Ashby
Data sciencey people — if you haven’t tried Positron, I highly, highly recommend giving it a whirl.
January 30, 2026 at 3:43 PM
Data sciencey people — if you haven’t tried Positron, I highly, highly recommend giving it a whirl.
A good example of how many public debates about violence don’t match reality:
Women in England and Wales are more than 10 times more likely to be killed in a dwelling by a partner/relative/friend than outside the home by a stranger.
Women in England and Wales are more than 10 times more likely to be killed in a dwelling by a partner/relative/friend than outside the home by a stranger.
Women were much more likely to be killed in a residence by someone they knew than a stranger in public. Each year about 8 women were killed by strangers in an outdoor public place, compared to about 90 women killed in a dwelling by someone they knew.
January 30, 2026 at 9:19 PM
A good example of how many public debates about violence don’t match reality:
Women in England and Wales are more than 10 times more likely to be killed in a dwelling by a partner/relative/friend than outside the home by a stranger.
Women in England and Wales are more than 10 times more likely to be killed in a dwelling by a partner/relative/friend than outside the home by a stranger.
Homicide (like all types of crime) is heavily concentrated in a small number of places – half of all homicides in England and Wales happen in six police-force areas. But where are different types of homicide most concentrated?
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January 30, 2026 at 3:00 PM
Homicide (like all types of crime) is heavily concentrated in a small number of places – half of all homicides in England and Wales happen in six police-force areas. But where are different types of homicide most concentrated?
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England and Wales has a much lower firearms homicide rate than in most large European countries, Australia and Canada. And obviously a vastly lower rate of firearms homicide than in the US.
(Also: no, we don’t have more knife homicides than they do, either.)
(Also: no, we don’t have more knife homicides than they do, either.)
Firearms homicides in England and Wales are very rare, with about 30 people fatally shot each year. That's lower than the rate of firearms homicides in most other European countries, Australia and Canada. It's also vastly lower than in the United States.
January 29, 2026 at 6:47 PM
England and Wales has a much lower firearms homicide rate than in most large European countries, Australia and Canada. And obviously a vastly lower rate of firearms homicide than in the US.
(Also: no, we don’t have more knife homicides than they do, either.)
(Also: no, we don’t have more knife homicides than they do, either.)
Reposted by Matt Ashby
People living in England and Wales are much less likely to be victims of theft than in the 1990s—
Several data sources show that theft in England and Wales has declined in recent decades.
One of those is police records — but they only capture reported crimes, and many people don’t report thefts.
Several data sources show that theft in England and Wales has declined in recent decades.
One of those is police records — but they only capture reported crimes, and many people don’t report thefts.
January 29, 2026 at 3:52 PM
People living in England and Wales are much less likely to be victims of theft than in the 1990s—
Several data sources show that theft in England and Wales has declined in recent decades.
One of those is police records — but they only capture reported crimes, and many people don’t report thefts.
Several data sources show that theft in England and Wales has declined in recent decades.
One of those is police records — but they only capture reported crimes, and many people don’t report thefts.
An excellent article pointing out some of the issues with the government’s (generally good) police reforms.
For me, most important point: the reforms will likely only work for local communities if they manage to combine strong local operational independence with greater back office centralisation.
For me, most important point: the reforms will likely only work for local communities if they manage to combine strong local operational independence with greater back office centralisation.
Labour's policing white paper has a lot of good stuff in it - but also one big flaw. Some thoughts on the good, the bad and the 'are you sure about that one?' parts of it:
The case for Labour’s policing overhaul — and the big risks
Breaking down the good, the bad and the unclear in the government’s new white paper
www.ft.com
January 29, 2026 at 3:20 PM
An excellent article pointing out some of the issues with the government’s (generally good) police reforms.
For me, most important point: the reforms will likely only work for local communities if they manage to combine strong local operational independence with greater back office centralisation.
For me, most important point: the reforms will likely only work for local communities if they manage to combine strong local operational independence with greater back office centralisation.
Every year about 600 people are killed in homicides in England and Wales. But how are people killed, and how does it vary for victims in different groups?
This thread summarises what we know about how often different methods are used in homicides.
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This thread summarises what we know about how often different methods are used in homicides.
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January 29, 2026 at 3:00 PM
Every year about 600 people are killed in homicides in England and Wales. But how are people killed, and how does it vary for victims in different groups?
This thread summarises what we know about how often different methods are used in homicides.
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This thread summarises what we know about how often different methods are used in homicides.
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Homicide offenders are almost always men. But homicide offending is concentrated in other ways, too: while unemployed White men aged 20–49 make up less than 1% of the population but more than a quarter of all homicide offenders.
Homicide offenders are almost invariably men.
93% of convicted homicide offenders were male. 65% of cases involved male victims killed by male suspects, 26% of cases involved female victims killed by male suspects, and 4% of cases involved male victims killed by female suspects.
93% of convicted homicide offenders were male. 65% of cases involved male victims killed by male suspects, 26% of cases involved female victims killed by male suspects, and 4% of cases involved male victims killed by female suspects.
January 29, 2026 at 12:35 PM
Homicide offenders are almost always men. But homicide offending is concentrated in other ways, too: while unemployed White men aged 20–49 make up less than 1% of the population but more than a quarter of all homicide offenders.
Each year about 730 people are charged with a homicide offence in England and Wales. But who are they?
This thread summarises what we know about who commits homicides and in what circumstances.
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This thread summarises what we know about who commits homicides and in what circumstances.
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January 28, 2026 at 3:00 PM
Each year about 730 people are charged with a homicide offence in England and Wales. But who are they?
This thread summarises what we know about who commits homicides and in what circumstances.
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This thread summarises what we know about who commits homicides and in what circumstances.
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Black teenage boys are 13 times more likely to be killed in a homicide in England and Wales than White boys of the same age.
Black men and boys are particularly likely to be victims of homicide: a Black boy aged 10–17 is 13.4 times as likely to be a victim of homicide as a White boy of the same age.
January 28, 2026 at 11:26 AM
Black teenage boys are 13 times more likely to be killed in a homicide in England and Wales than White boys of the same age.
Each week, about 12 people are killed in homicides in England and Wales. But who is most likely to be killed?
This thread summarises what we know about who is most likely to be a victim of homicide.
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This thread summarises what we know about who is most likely to be a victim of homicide.
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January 27, 2026 at 3:00 PM
Each week, about 12 people are killed in homicides in England and Wales. But who is most likely to be killed?
This thread summarises what we know about who is most likely to be a victim of homicide.
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This thread summarises what we know about who is most likely to be a victim of homicide.
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The homicide rate in England and Wales is about one fifth of the global average, and about one third of the average for high-income countries.
The US homicide rate is six times higher than ours.
The US homicide rate is six times higher than ours.
Looking further afield, the homicide rate in England and Wales is about one-fifth of the global homicide rate and about one-third of the average rate in other high-income countries. The US homicide rate is about six times higher than ours.
January 27, 2026 at 11:34 AM
The homicide rate in England and Wales is about one fifth of the global average, and about one third of the average for high-income countries.
The US homicide rate is six times higher than ours.
The US homicide rate is six times higher than ours.
England and Wales currently have some of their lowest homicide rates since the 1970s:
Homicide in England and Wales is rare, and getting rarer. The homicide rate increased continuously from 1960 until 2000, then dropped substantially until 2016. After a brief increase, homicide has now dropped to the lowest level since the 1970s.
January 27, 2026 at 10:37 AM
England and Wales currently have some of their lowest homicide rates since the 1970s: