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A Guardian Technology campaign for free public access to data about the UK and its citizens


Crime mapping for London, Boris? We’ll start the clock now

Boris Johnson’s election as mayor of London means that we can see how committed – and effective – the Tories are in their claims to want to provide more data from councils and government to the public.

Among the pledges made by Johnson as part of his election campaign was to introduce crime mapping to London.

David Cameron, the Tory leader, wants every police force in the country to record every crime online, every month, in map form. There’s also a pamphlet (PDF) on their proposals.

How long will it take in London, Boris was asked? “We’ll start on day one, I’ll go to the Met and say listen, this is a fantastic idea…let’s see what we can do to put this on the web so people can look at exactly what’s going on in their neighbourhood, and use that tool to drive down crime.”

David Davis, shadow home secretary, says “the police will get a massive reduction in red tape, targets..”

Given that Boris didn’t get the final say-so until midnight on Friday, and Monday May 5th is a holiday, perhaps Tuesday will be the “day one” when he’ll stroll into New Scotland Yard and mention this. We’ll keep count. (Apparently he went to work on Monday. So the clock is well and truly started.)

If it arrives, it’ll certainly be a win for free data. Interesting questions: will it be on Google Maps or Ordnance Survey’s OpenSpace, or some other provider’s maps? Will it be redistributable? What sort of copyright will it have?

The proposals have considered privacy issues, and suggest:

We believe

there should be three kinds of map for each area for three categories of offences:

(a) where privacy is less of an issue: at their exact location with a pinpoint showing exactly where the offence occurred;
(b) where privacy might be an issue: identifying a 300 metre long street section within which an offence occurred; and
(c) where privacy is an issue: identifying the nearest whole street within which an offence occurred.

(Assaults would be in category (a); sexual attacks and domestic violence in (c), for example.)

The copyright issue – and reusability – may have been determined: from the pamphlet:

As our new regime spreads more crime information into the public arena, we expect people will want to create their own crime maps on the web of their own neighbourhood. That will be a matter for individuals, social entrepreneurs, Neighbourhood Watches and others. Once the appropriate statistics are freely available, it would be comparatively simple from a technical point of view for citizens themselves to overlay the statistics onto an online street map. There are already many different mapping systems of the UK available to the public online, including Yahoo, Google, and Streetmap.

But what about that terrible ogre for Britons – house prices?

It is sometimes pointed out that crime mapping, in identifying areas of high crime, affects the level of house prices in those areas. In fact, crime mapping can actually raise house prices if identifying areas where crime is rising then leads to effective action being taken to cut crime. In our view crime mapping will provide a clear and powerful incentive to affected residents to complain and insist on effective crime fighting solutions to reduce the crime. And when crime is reduced this typically increases house prices – rather than the reverse.

So, we’ll start the clock tomorrow at 8am, when mayors ought to be arriving in their offices to start work.

3 Responses to “Crime mapping for London, Boris? We’ll start the clock now”

  1. Malachi Rangecroft Says:

    The Conservative paper mentioned the West Yorkshire Police site http://www.beatcrime.info which was commissioned by the West Yorkshire Police Authority but supported by WY Police. It already shows the location of crimes and incidents but only at max accuracy of 1:50 000 scale. Part of the reason is accuracy of the data…we plan to improve beatcrime.info and include street level mapping, but this is combined with another project to improve the location element (x, y co-ordinates) of crimes and incidents that are recorded. Most Police gazetteers are based on AddressPoint (with some Police Forces working on projects to utilise the NLPG as the trusted data source for their gaz) but this does not provide enough detail for non-addressable locations. Many crimes & incidents might occur on a street corner, or at a bus stop, or by an ATM – find those in AddressPoint or even the NLPG! This leads to Forces having to purchase expensive additional data to complement their ‘addressable’ data in an attempt to create a do-it-all gazetteer – needed for street level data points at the scale Boris envisages. The Police are working on a National Emergency Services Gazetteer project to create a definitive gaz, but this will take time, resources & money. Good luck to the Met if Tuesday is indeed the starting point for the implementation of accurate crime mapping on the web! But this may just be the required incentive to help the Police (and other Emergency Services) get the complete gazetteer they need for operational purposes, to aid in timely resource deployment and accurate crime mapping…

  2. Simon Dickson Says:

    It won’t be easy. A year ago I approached the local police, requesting this data for use in building a proposed community website. A relatively informal request, not a full-on FOI demand or anything. They politely refused, on the grounds of confidentiality and resources. They wanted to protect victims’ privacy, and didn’t have the data in the sort of format I was after anyway. It seemed reasonable, and I didn’t have the energy to push harder.

    Boris could succeed here, because: a) it was an explicit manifesto commitment, b) he’s dealing with a single large-scale entity, and c) he has some degree of management oversight of them. And that could open the floodgates for other initiatives elsewhere.

    On Malachi’s comment… Whilst I’m no expert, I’m not sure the lack of a gazetteer should be a hurdle. The Google Maps API, for example, includes a function to echo back the centre point of the map view you’re looking at. So you simply overlay a crosshair on the centre point, and tell people to zoom/drag the map (or sat view) to where they want. Bingo, you’ve got your long/lat coordinates. I’ve done this on several projects, and it works great.

  3. Colin Drane Says:

    Crime mapping is a relative simple task provided that you’ve got available data. Privacy issues can be handled easily by blocking addresses and marking the crime in the nearest block or intersection. Even if the data is in paper report form, my company, Spotcrime (dot) com, can manually code 1,000 crime incidents daily. Depending on the format, we could have a working map of London crime incidents within as little as two weeks. Within a month, we could be providing crime alerts to anyone requesting them.

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