In the 21st century, the idea that people with serious criminal records can avoid monitoring by simply crossing borders is as surprising as it is deeply worrying.
Most observers would not expect it to be so easy for ex-offenders who have been found guilty of sexual or violent crimes to start again out of sight of the authorities, especially when they were subject to legal restrictions in their home countries.
That appears to be the situation which has been exposed by the rape and murder of mother-of-three Mary McLaren in Dundee in February 2010. She was killed by Patrick Rae, who was a registered sex offender in Ireland but not automatically obliged to make himself known to authorities in the UK.
A review carried out by Lothian and Borders Police into the circumstances of the Rae case has called for new laws to require foreign nationals to reveal their convictions on entering the country.
This call is backed by Beatrice Jones, the mother of another victim. Her daughter Moira was raped and murdered in Glasgow by Slovakian, Marek Harcar, who had 13 previous convictions, including four for violent offences. Mrs Jones describes the Lothian and Borders proposal as common sense, and in the interests of crime prevention.
The question is not about a lack of information. As Mrs Jones points out, the European Criminal Record Information Service (ECRIS) is a major step forward, and has theoretically given forces across Europe access to each other's information about criminal records. However, forces need to know to ask for the information, and need to act on it when it is received.
In the case of Rae, Dumfries and Galloway constabulary appears to have badly dropped the ball by failing to seek an order which would have allowed them to impose restrictions on Rae, once they had learned of his past. It appears they are not obliged to do so – that decision is up to the relevant chief constable.
Police should be obliged to seek controls over offenders once they are known to the authorities here, as long as their offences would have met the requirements for monitoring under Scottish laws.
There must also be questions about whether the system can respond quickly enough when they do so. When he moved to their area, Grampian Police did seek an order for restrictions on Rae, but by the time this had been obtained it could not be served on him because he had slipped off the radar.
It is useless to demand new arrivals declare convictions at points of entry if the necessary restrictions are not then imposed.
There will always be difficulties due to the variations in approach in different jurisdictions. In some European countries, for example, sentences for indecent assault on children are much shorter than here, and convictions which result in sentences of less than three months are wiped after as little as three years.
But this is clearly a loophole. It may well be that legislation is needed, but in many ways the necessary infrastructure is already there. With the introduction of ECRIS in April, it shouldn't be impossible to ensure dangerous criminals are automatically flagged up. This would allow British authorities the maximum possible time to put suitable monitoring in place.
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