Thread by @JeSuisTC

Looking at models for #forensic science provision in England and Wales, there are some immutable truths, namely, geography, population density and crime rates (which are a reflection of both) /1

This is the map of the 43 police forces in E&, its been this way roughly since 1972, which was a great improvement on 1946 when there were 117 police forces 👀 /2

the map tells us little other than where one police force ends on one begins. Lots of ways to look at population density, I like this one which plots it by 5x5kmsq. No surprises, it's the UKs immuatble truth #1, big cities, urban sprawl and the countryside /3

it's not a surprise then that crime rates by area are largely affected by population density. More people, generally speaking, means more crime. /4 ons.gov.uk/peoplepopulati…

what does this all mean for a model for #forensic science provision? Well you want to make sure that the forensic resources in the system are at a minimum sufficient to meet the demand. /5

Demand is a function of the crime data, it is not a variable controlled by a police force. That's immutable truth #2 /5

Geography matters though. No point in having one forensic DNA lab for England and Wales because turnround times for DNA samples will become a function of the distance from the laboratory. This matters for DNA because police forces often need a result <24hrs. /6

using up 6-8 hrs of the 24hrs merely getting a sample to the laboratory would be unacceptable. If you were in the north east and the lab is down south, you'd be better off sending it to Scotland. /7

So whilst having one massive forensic lab somewhere in E&W that does everything is attractive from a cost point of view, (imagine the reduction in accreditation costs) it is not a practical proposal. /8

But not all forensic activities require a fast turnaround time either because there is no real demand for speed in the criminal justice system or because the activity requires a longer time to complete than it takes to process a swab for DNA. /9

for example a case where a suspect has been identified and is in custody, and the investigation moves from identification to "evidential", where the prosecution attempts to build a case. The demand for speed is relaxed if the suspect is no longer at large and posing a risk. /10

the demand for speed because the police have done nothing in a case for three months and suddenly face the case being thrown out of court, is not a proper criteria to rely on which to build a model for a national #forensic service. All models depend on functioning partners. /11

It is possible therefore to classify the resource need by activity and its likely demand for urgency. If the activity takes a long time and resides largely in the "evidential" part of the process, then transport time of evidence to a laboratory is less critical /12

on that basis there is an argument that for some activities, that one lab in England and Wales might be enough in terms of delivery of results on time. /13

the argument for such a lab(s) is strengthened from a financial point of view for activities requiring expensive equipment, such as trace evidence and toxicology. Better to have one well-equipped modern lab kept up to date than several labs with old or broken equipment. /14

I'm only scratching the surface, but the model is clearly not as simple as having x labs covering y areas all doing the same stuff. /15

any model for a national service like this has to divvy up resources in some way and put them somewhere practical The police force map doesn't make that easy. The Home Office and the police have helpfully done some of the work already though. They class themselves by region /16

Here they are, there are 10 regions (displayed here in terms of recorded crime numbers). I suspect their classification into regions came from the last aborted attempt in 2006 to merge forces together, but I may be wrong. 10 from 43 sounds like good business to me though. /17

On that basis the picture of recorded crime in ascending order,by region, looks like this. On that basis, it would be reasonable to assign a minimum of 1 unit of "forensic resource" to any region with above 400k worth of recorded crime. /18

that leaves Wales, NE, SW and EM short. For the remote coastal regions this was always going to be an issue. EM is only short as a result of map drawing and is arguably viable with 375K crime. If Wales and the NE merge in some way with other regions, the model takes shape. /19

From a geographical point of view no point in just shifting all of Wales somewhere, so in terms of a "forensic resource unit" southern welsh forces move to the SW, Dyfed Powys to West mids and North Wales forces to NW. NE forces to Yorks. /20

the inescapable conclusion to this is that each of these regions needs its own regional forensic organisation, IMO each must be independent of the police. It doesn't matter how you slice it, the FSS got this right. The labs were in the right places to service the demand. /21

I am not recommending an FSS model. I completely understand criticisms of models on the basis that it sounds like the FSS, but it would be foolish to dismiss aspects of the FSS model that worked. /22

if you look at the UK as a whole, this approach would bring E&W in line with Scotland and Northern Ireland in terms of a "unit of forensic resource", although E&W regions would be larger, politically they all command equal standing in the national forensic picture. /23

On that basis, the model for a UK national forensic service comprises Scotland, NI and 8 regional forensic organisations from England and Wales /24

Looking at NI and Scotland as labs operationally independent from each other (and everyone else) it would make sense to me that the 8 regional organisations in E&W were independent too, free to decide how a forensic service is run for their region. /25

All of course whilst operating a consistent level of high quality and best practice. Regional organisations should have the freedom to innovate, to use different approaches, as long as the quality is not put at risk. /26

you'll be relieved to know that's as far as I've got for now. Next stage is to look at the regional organisation in more detail based on activity and demand. this still remains a "blank paper" approach for now, i.e. if you had to start a forensic service from nothing. /27

it will end up with an ideal model, after that it will be tested against the practicalities of changing where we are now, to where we may like to get to and how that might work /28 /ends

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