It happened right here!

The level and timeliness of information available to the public on crimes occuring in their neighbourhood is now quite astonishing. In the US spotcrime.com uses a mash-up of police records and Google Maps to provide detailed maps of the precise location of seven types of crime (theft, burglary, robbery, assault, arson, shooting, vandalism), plus the location of arrests. For those unsure of the differences between some of these (and I was never fully sure of the difference between theft, burglary and robbery) they are:

• Theft - taking property belonging to another without that person's consent.
• Burglary - breaking and entering a building illegally for the purpose of committing a crime.
• Robbery - using force or intimidation to take property away from another person in the presence of that person.
• Assault - a physical attempt or threat to use violence with the intent to do harm to another.
• Arson - intentionally setting fire to the property of another or the burning of one's own property to collect insurance.
• Shooting - firing a weapon in order to hit, wound, or kill someone or something.
• Vandalism - the intentional destruction of or damage to the property of another.

If you hover your cursor over a crime location a little box pops up and tells you the nature of the incident that occured there. In some cases it will even tell you the name of the perpetrator and details about them. The map seems to be updated daily and certainly weekly so you can get a pretty much real time view of the crimes occuring in an area.

The map above (click to enlarge) shows downtown Boston and parts of Cambridge for between 4th June and 4th August. Robberies seem to be most prevalent in the downtown; there are a cluster of burglaries around Columbus Park; a fair few thefts in Cambridge; and a cluster of assaults in Cambridge near to MIT and around Lower Roxbury.

Crimespot also provide maps of crimes in cities all round the world (including a search facility for those not listed) I'm not sure of the source of the data for some places. In Dublin, Ireland, the address data seems to be stripped out of newspaper reports. Crime data in Ireland, as far as I am aware, is hampered in two respects. First there are no postcodes in Ireland making it difficult to record its precise location, and second, as a result, crime is recorded against the responsible garda station not its location. The result is it is extremely rare to see meaningful maps of crime in Ireland at a local scale.

For those living elsewhere you might be able to view what crimes are occuring in your neighbourhood. How to interpret this data or its uses is a whole other ball game. Perhaps I'll cover that in another post at some point.

Mapping Murder

I browsing Adrian McKinty’s blog at the weekend and he had a post about an interactive map of homicide in New York. His post mainly concerns the fact that 88 percent of the victims are black or Hispanic and how this reality isn’t reflected in TV cop shows. What I found interesting though was the map itself and the geography of the murders and how the deaths were mapped with respect to the race, sex and age of the victim and perpetrator, weapon used, year committed, and so on, to reveal distinctive patterns concerning the social and racial make-up of the city.

The map below clearly shows a geography to the race/ethnicity of the victim, with most of the victims in Brooklyn black; a strong concentration of Hispanic deaths (in Jackson Heights) and a small cluster of Asian deaths (in Flushing) in Queens; a mix of black and Hispanic victims in Harlem and the Bronx; and a fairly even mix of white, black and Hispanic murders in Lower Manhattan.

This kind of mapping is very common in just about every police force in the Western world at this stage, with each divisional command having its own GIS (Geographic Information System) intelligence unit that maps all crimes with its associated data (crime type, victim and perpetrator details, weapon, drug type, etc) and seeks to understand the patterns in order to help solve cases, allocate police resources, target crime hotspots, help profilers, calculate emergency response routes, and so on.

The three maps below are generated using a commercial GIS crime package – Mapitude – and plot the location of sex offenders vis-à-vis school location; motor theft hotspots; and change in the property crime rate over time (clicking on the image should enlarge it).

Given I’m fascinated by maps, as and when I come across some interesting ones relating to crime, I’ll add them to the blog. If anyone has any pointers to other interesting crime maps I would be delighted to receive them.