Tuesday, 22 September 2015

Big Brother Needs Bigger Batteries

Following on from my report about Electronic Monitoring from the Leicester conference last week, I see that the right-wing think tank Reform have given the MoJ another good kicking over the complete Horlicks they've made of the new tagging contract:-     

Cutting crime: the role of tagging in offender management

On any one day up to 25,000 people are subject to electronic monitoring (EM) in England and Wales, largely as part of a Community Order, Bail Order or post-release licence condition. In the last few years pilots have also been undertaken to test the impact of EM in tackling domestic violence, alcohol-related offending and prolific and priority offenders.

As technology has advanced, so too has the potential of ‘tagging’. The original radio frequency technology monitors whether an offender is in a particular location at a particular point in time, the global positioning system (GPS) technology allows continuous monitoring of an offenders location. Transdermal alcohol tags can continuously test the alcohol level in an offender’s perspiration. As with any technology there are limitations, but as shown in America, if used effectively EM has the potential to help reduce reoffending and cut criminal justice system costs.

The potential of EM has, however, been undermined by the Ministry of Justice’s poor procurement of the ‘new generation’ of tags. At best it will have taken four and a half years to deliver the GPS tags, and even when they are delivered the contract model will stifle innovation.

The report recommends that the Government:

  • scrap the current procurement and establish a framework of approved suppliers for local services to contract with;
  • extend the use of tagging to police bail, domestic violence related orders and serious offenders leaving prison on early release; and
  • ensure frontline criminal justice practitioners can use the data generated from GPS tags to detect and prevent crime.
--oo00oo--


Whilst acknowledging that although the evidence might be lacking, tagging lots more people would make all kinds of sense commercially and save the government shed loads of money, there's just the small matter of battery life - the tags need to be plugged in every few hours:-

1.6 The limitations of electronic monitoring 


EM technology has evolved considerably, enabling increasingly sophisticated use as an offender management, punishment and public-protection tool. As with any technology, however, it has its limitations. In addition, this advancement in technology has raised concerns about the collection and use of increasing volumes of data. It is important for policymakers and practitioners to recognise these. 

1.6.1 Battery life 

As pressure rises to ensure GPS devices run more and more concurrent capabilities, the battery life reduces significantly. In addition, increasing volumes of data transfer drains the battery life of a device. Continuously tracking offenders to provide real-time intelligence requires much more frequent communication between the electronic anklet and central portal. Interviews for this report suggest that this type of tracking can reduce a tag’s battery life to just a few hours. 

In response to this problem some providers have developed a portable charging pack which can be clipped on to the electronic anklet. This negates the need for the offender to be near a charging socket if the battery runs low. 

1.6.2 The robustness of the data 

The accuracy of GPS data has greatly improved, however there continues to be a number of limitations. 

Drift 
The strength of a GPS signal can vary depending on the distance to the nearest satellite. When the signal is particularly weak this can cause drift. Drift, or movement in the accuracy of the signal, means that an offender may be recorded some distance from their true location (although this will often only be a matter of meters). When a subject has a number of inclusion or exclusion zones it is possible a violation can be registered. To combat this, ‘buffer zones’ can be built in to provide offenders and monitoring agents with an early warning that they are close to committing a violation.

The Scottish Government’s 2013 consultation on EM also highlighted that drift can occur when a subject remains stationary for a prolonged period and is close to water.

Whilst drift can be problematic it often does not, however, exclude a data set from being used as evidence of a violation. Generally only a minority of the data points in a series will be inaccurate, so by reading the set as a whole it is still possible to see the direction an offender was travelling and exclude the anomalies.

Cities and rural areas 
A GPS signal can be disrupted in built up areas where very tall buildings can block the satellites and cause the signal to bounce. Similarly, much like many smart phones, GPS tags may be less accurate in very rural areas. Whilst the GSM mobile phone network can be used as a backup when GPS signal is unobtainable, the level of accuracy provided by the substitute system is much lower. As GPS coverage improves across the country this will become less of an issue. 

Underground 
A particular problem for EM use in London is the lack of GPS signal on the Underground. Whilst agents can contact subjects approaching a tube station to confirm their travel plans and estimate a reasonable journey time before a signal should resume, the offender’s whereabouts cannot be confirmed for the duration of that journey. 

GPS jammers 
In addition to these geographical issues, GPS ‘jammers’ can be used to block or interfere with the GPS signal. It is not currently illegal to import, sell, buy or possess a jammer in the UK and basic jammers are easy to acquire. Experienced monitoring agents interviewed for this report have suggested that it is possible to identify when a jammer has been used, however there is a risk that an offence is committed before the jammer is identified, or that the offender has absconded in that time.

Tampering 
As well as deliberately blocking the GPS signal, offenders’ efforts to remove or damage the hardware of the tag can cause problems. 

Whilst a fibre-optic cable within the strap will alert the relevant authority if the tag is cut or tampered with, it does not prevent offenders who have successfully removed their tag from offending or absconding. The high profile case of Mohammed Ahmed Mohamed,46 who absconded whilst subject to a Terrorism Prevention and Investigation Measure (TPIM), demonstrates this. Here, the technology had not failed and a tamper alert had been sent to the monitoring centre, but a delay between the alerts and the police arriving still allowed the offender to abscond. 

1.6.3 The accessibility and usability of the data 

Interviewees for this paper raised concerns that data collected by the National Offender Management Service (NOMS) from the new generation tags will not be accessible for police and the Crown Prosecution Service. This inhibits the potential for the tags to be used not only for enforcement, but also to prevent and detect crime. Overlaying EM data with crime data could also enable more effective and efficient deployment of criminal justice system resources. 

This, however, raises privacy issues. Whilst it is desirable for multiple agencies to be able to exploit the intelligence harvested from GPS monitoring, it must be done within appropriate legal frameworks. It is important to consider not only the highly personal nature of the data being collected, but also that in some instances the information is being taken from victims – when being used for domestic violence tagging – or those on remand who have not been convicted of a crime. 

In Germany, data collected is erased after just two months, and must only be used where the offender has been convicted of a crime that is punishable with at least a year in prison. If the benefits of GPS enabled EM are to be fully realised, replicating this approach would be too restrictive. Nonetheless, there must be a clear and transparent framework identifying who can access the data and under what conditions.

13 comments:

  1. Over the years governments and private companies have been desperate for more tagging. Privatizing probation was suppose to solve this.

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  2. Jim what's this nonsense article? Do better. What's happening at NAPO AGM?

    ReplyDelete
    Replies
    1. If you don't like it mate - go elsewhere :)

      Delete
    2. I'm not your mate. We're foe

      Delete
    3. We're be mates once you start blogging some decent blogs :)

      Delete
    4. Just to say there's quite a bit more of the same coming down the line and puerile comments such as the above will have absolutely no effect on what I decide to post or not.

      Sensible, useful comments are always welcome, but not necessary. The hit rate is still ticking over at 3,000 a day so I assume some people at least are finding something worth reading. Thanks go to every one of these people for their ongoing support and interest.

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    5. Write to napo and ask you fool

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  3. As a CDO I ( and all of my colleagues) have repeatedly advised the Court that individuals were not suitable for tags due to being DV perpetrators or victims. This appears to stand this on its head! What's changed?

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  4. Technology? What's wrong with drones, death rays & mind control? Why spend mega credits on amateur battery powered bracelets when we could simply eliminate transgressors with Chinese sponsored nuclear powered neutralisers?

    Oops, it isn't 2021 yet. Prepare yourself for the 2020 campaign by President Boris.

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  5. I must correct you on your technology.

    The accuracy of GPS data has greatly improved, however there continues to be a number of limitations. 

    Since its inception 30 odd years ago GPS has been very accurate one part in ten to the minus ten based on an atomic clock and they have not improved. From the very first the accuracy was such that oil rigs could be positioned over wells, cable layers pick up cables.

    The strength of a GPS signal can vary depending on the distance to the nearest satellite. When the signal is particularly weak this can cause drift. Drift, or movement in the accuracy of the signal, means that an offender may be recorded some distance from their true location (although this will often only be a matter of meters). 

    The satellites are in circumpolar orbit, you need to be receiving three or four to get a good position. They are digital, if the signal strength is strong enough you will receive its message, its an either do or don't but the strength of the signal as long as its above a threshold makes no difference to the position.

    Drift, or movement in the accuracy of the signal, means that an offender may be recorded some distance from their true location (although this will often only be a matter of meters).

    I have not heard of GPS Drift before, I looked it up and it refers to a stationary GPS reporting different positions. Early GPS did not have this problem. They were expensive and had a crystal oscillator kept at a constant temperature in an oven. This oscillator would be accurate to one part in ten to the eight. Very impressive a room full all showing the same position or adjusted for which side of the room. Modern much cheaper GPS will not have crystal ovens, they will maintain accuracy to one part in ten to the six. Most likely the drift is caused by a cheap oscillator drifting off frequency between synchronizing with the satellite clock.

    The biggest problem with GPS is that GPS coordinates are different to your maps datum, you must apply a correction which can be in the order of a 100 meters.



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  6. The original radio frequency technology monitors whether an offender is in a particular location at a particular point in time, the global positioning system (GPS) technology allows continuous monitoring of an offenders location. batteroo inc

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