Blunkett's satellite tagging: the tripe behind the hype
Home Office redefines statistical invalidity
Today's announcement  of the Home Office's satellite tracking pilot is a classic of its genre. As is the case with so many Blair government initiatives the earth was noisily promised in the run-up, and continued to be promised by government spokesmen this morning, but the pilot itself is so spectacularly modest, so largely low-tech, that it will provide little or no useful information about the viability of the "prison without bars" that David Blunkett will continue to dangle before our eyes through the upcoming election campaign.
So, as the nonsense flows from the Home Office over the next 12 months, just you remember that the tech tinkering cannot and will not take the Home Office's 5,000 most prolific offenders (as specified in its Strategic Plan ) out of circulation by putting them into a virtual pen. Tagging and tracking is (as will become clear in the years following the next election) at best a system that can be used on a relatively small scale in conjunction with early release and rehabilitation schemes for offenders who want to be rehabilitated.
The 12 month trial will cover 120 offenders in three areas, Greater Manchester, Hampshire and the West Midlands, and despite what you've read practically everywhere, it will not track them 24 hours a day. Log 'em, yes, but that's not quite the same. The latter two areas will test passive tracking only, while Greater Manchester will test what the Home Office calls "hybrid tracking". Which clearly calls for an explanation.
Passive tracking uses GPS to log the movements of the subject onto the device that the subject is wearing, but there is no realtime monitoring of the subject's whereabouts. So in two senses you could call it a laglog. At specified times (typically, in the evening at home) the device is connected to a base station which then transfers the log data to the monitors. We at The Reg have not seen one of these lists of GPS coordinates, but we're sure that probation officers will find them deeply exciting reading. Not. Presumably they're just automatically compared with coordinates redzoned for the individual, and alerts are issued accordingly, while the data can also be used to check whether the subject was in the vicinity of any reported crimes.
"Hybrid" tracking is largely passive as well, but goes into active mode and sends a realtime alert should the subject enter an exclusion zone. All three of the test areas will be tracking prolific and domestic violence offenders, while Hampshire will also test the system for young prolific offenders, and Greater Manchester for sex offenders. We can therefore assume that hybrid will be used on the sex offenders, and considering the small total numbers that it won't be used on more than a handful of individuals.
The actual kit works like this. The subject is fitted with an ankle tag which wirelessly communicates with a GPS tracking system worn on the belt, or similar. GPS itself doesn't work anywhere where it can't get a fix on the satellite (i.e. indoors, and it's likely to be at least problematic in built-up areas), but as the tag-GPS link ought still to work in such circumstances the monitors will have a backstop of sorts, in that there will be a high probability that the subject is still wherever they went into when they vanished from GPS.
We doubt very much if the Home Office will be recruiting volunteers with the specific brief of trying to subvert the system, but it seems to us that this would be a very good idea, because you really do have to try to anticipate what those 5,000 villains are going to try when the thing goes live.
But there are a few obvious ones. First, anybody who wants to scarper can. Just snip the bracelet off and run for it - if the bracelet is sufficiently alarmed for it not to be feasible to remove it without it stopping working or sending an alert, then move out of GPS service before doing this. If it turns out that you can get it off without it noticing, then you could be creative, bag up both devices and pop them onto the back of a lorry heading for Inverness.
No doubt the Home Office will tell us that the system isn't intended to be used on anybody likely to try to run for it, but if that's the case it should really stop calling it a prison without bars, and trying to convince the public that technology will be able to tame the most dangerous criminals - it won't, clearly. Alternatively, it could just be clearer that by "prison without bars" it means one you can walk out of whenever you want.
Attempts to subvert the system while apparently remaining within it will likely be a lot more common. The trick, we presume, will be to break the GPS coverage without breaking the link between the GPS device and the bracelet, but this should be a relatively simple low-tech task. Go somewhere out of GPS service where you might plausibly spend a few hours, block the GPS, then you can safely pinch motor cars or murder your former wife while having some form of alibi. It's not absolutely definite you weren't there, but it certainly looks like you weren't.
We presume the UK's 5,000 most prolific offenders are not in general very bright, otherwise they wouldn't keep getting convicted. If however you're going to tag the lot of them then you're going to be creating a ready market for rather more sophisticated subversion. GPS can be spoofed, so some kind of rig that keeps the device sending "I'm in Wolverhampton" while you're bludgeoning your ex in downtown Manchester is perfectly feasible. And it shouldn't be beyond the wit of man to duplicate whatever the bracelet is sending to the belt, thus convincing the belt that the bracelet is in Wolverhampton while it's really at the scene of the ongoing crime. As we keep saying, these systems will only work on people who actively want to cooperate and be rehabilitated, and aren't applicable on a wide scale to people who just want to stay out of prison while carrying on their life of villainy.
The monitoring is worth considering, and the nature of the pilots tells us a great deal about how the systems will be employed in the long term. As the "hybrid" tracking can send an alert when it wants to, there's clearly no technical reason why it could not we used for 24 hour realtime tracking. So it is not being used for this specifically in order to simplify the monitoring task drastically, avoiding situations that require large numbers of personnel at the monitoring end and that are likely to produce false alarms. If it's being used for paedophiles then it will simply send an alert if the subject goes near a school (Why, incidentally, do people think this kind of redzoning is any use? Does any supporting data exist?), and there's no great need for any expensive control rooms.
The monitoring of the passive tracking has more obvious utility, because it's a logical, possibly even a viable, extension to what we're doing already. The Home Office has already used tagging for the enforcement of curfews and similar on a fairly widespread basis, and this has been relatively popular in that it has helped keep young offenders out of prison and in rehabilitation programmes. So the Hampshire test covering young prolific offenders is particularly important, as it should give the Probation Service a greater degree of certainty that the the subjects really are staying out of trouble. Note however that this is the area where tagging has expanded most dramatically already, and that it will continue to expand whatever the results of the pilots.
Which is good news for the contractors. These are Securicor , Reliance  and Premier Geografix . Premier itself is now a subsidiary of Serco, and a sister company already runs a clutch of UK prisons and sundry detention facilities. We're not sure if the pic on Serco's site is of the board, some offenders undergoing corrective services or the national crime squad, but whoever they are they're certainly a bunch of ugly bastards. 
Blunkettwatch: In a piece about Debbie Melnyk's forthcoming film Citizen Black in today's Guardian , Melnyk reveals that guests filmed entering the disgraced former press baron's summer party included "Prince Andrew, Nigella Lawson, David Blunkett, Elle Macpherson, Imran Khan, David Furnish, Jemima Khan and Anne Robinson." What interesting company our David keeps. ®