Matt Ashby

I help people use data to reduce crime. Associate Professor at @UCLCrimeScience. Former police officer.

[Matt Ashby @LessCrime]

Most street violence occurs in a small number of hotspots. New research shows hotspots (🇺🇸) are connected by (the same offenders using) the same weapons across hotspots, with nearby hotspots and those with similar ethnic makeup being more connected.

https://t.co/2YS8iM7MwO

[Matt Ashby @LessCrime]

@BrokenBarnet That’s interesting. When I’ve seen them doing this, it’s always been the same bright red vans with a big rack of equipment on the roof. Do you have any pictures?

[Matt Ashby @LessCrime]

@BrokenBarnet If you were filmed during a police live facial recognition operation, you would very likely have been aware of it – they use a bright red van that has ‘live facial recognition’ written on it. They also put signs up on the street. Is it possible you were filmed by somebody else?

[Matt Ashby @LessCrime]

@BrokenBarnet I agree that the question of value for money needs more work. The level of intrusion, though, is minimal: the false-positive rate is very low, and if a person’s face doesn’t match a face on the list of wanted offenders, the picture is deleted immediately.

[Matt Ashby @LessCrime]

Interesting framework on how police (🇬🇧) are likely to use different AI tools in future, and the different ethical and reputational issues that creates. Good to see the Met having this debate at least somewhat in public.

https://t.co/zj9p1rnChs

[Matt Ashby @LessCrime]

Routine arming of police (🇦🇺) didn’t lead to any change in the rate at which police shot people.

This study doesn’t look at other potential consequences such as officer suicides using their firearm, which has been a consistent problem in Australia.

https://t.co/gsbOiA0aj9

[Matt Ashby @LessCrime]

@k3nnysm1th @JJSharpers No. Detaining a violent suspect normally takes more than one officer, for a start.

[Matt Ashby @LessCrime]

@GazTheJourno Not sure I understand how this is TfL’s fault? They don’t operate the tunnels that flooded. Obviously the Piccadilly line was coincidentally closed for engineering works, but they have to do engineering works some time and could hardly have known the tunnel was going to flood.

[Matt Ashby @LessCrime]

Police body-worn video recordings (🇺🇸) were associated with faster investigation times and (for some crime types, e.g. domestic abuse) less chance of prosecutors discontinuing a case, but little change in the likelihood of conviction.

https://t.co/xDBJugiQGG

[Matt Ashby @LessCrime]

@ChelseaBridgeWh @tomcopley @oldoakparkroyal @howarddawber @KarenPBuckQP If London boroughs were good at working together on projects, quite a few current London problems that wouldn’t exist. Sadly, they aren’t generally much good at working together. Hence the need for mayoral development corporations.

[Matt Ashby @LessCrime]

@cbchodgson @docmilanfar If a high level of maths is required for admission, the fact that most empirical economists are good at maths sounds very vulnerable to survivorship bias, doesn't it?

[Matt Ashby @LessCrime]

@ChelseaBridgeWh @tomcopley @oldoakparkroyal @howarddawber @KarenPBuckQP The site is partly in three different boroughs (Brent, Ealing, Hammersmith & Fulham), which is part of why they created a Mayoral Development Corporation.

[Matt Ashby @LessCrime]

@DavidJackmanUK @philatrail In what way? Doesn’t any replacement bus have to call at all stations anyway, in case any passengers want to be picked up?

[Full Fact @FullFact]

Social media posts claiming that Dorset Police said 44% of sex offences are carried out by asylum seekers living in asylum hotels are false.

We could find no evidence this is true. Dorset Police told us the figure is “incorrect” and was not issued by them.
https://t.co/EIqG7r7yaq

[Matt Ashby @LessCrime]

@AnupamChander One possible indirect mechanism: student evaluations give the instructor the information necessary to improve their teaching, which eventually leads to better teaching and higher grades.

[Matt Ashby @LessCrime]

@BenLiddicott @FaringForwards @trotter_alex @Ameer_Kotecha Are you, by any chance, reading the adult sentencing guideline?

[Matt Ashby @LessCrime]

@Nlcwrites @ShruggedAslef @mxmsworld @TfL A pay-as-you-go Oyster card can easily be tracked every time it’s used. That can then be linked to CCTV or card transactions used to top it up. Fortunately, the government isn’t generally interested in tracking you unless you’ve committed a crime. They’ve got better things to do.

[Matt Ashby @LessCrime]

@Off_The_RailsUK @maxwell_marlow @BTP @LNER I obviously don’t know the details of any incidents you were involved in. But if you feel you were let down, the best thing to do is to make a formal complaint. That way the police can improve for next time.

[Matt Ashby @LessCrime]

@Off_The_RailsUK @maxwell_marlow @BTP @LNER BTP arrest about 9,000 people a year, so they ‘do something’ quite often. You might like there to be more BTP officers, but claiming they do nothing is just silly.