In the 12 years since the national DNA database was inaugurated, our four police forces have contributed to it more than 260,000 profiles, we learn, courtesy of figures obtained by the Welsh Lib Dems.
This figure amounts to getting on for 10% of the resident population, if indeed these are the people recorded.
So either we have a very large criminal population or a very large criminal population is offending and being caught in Wales.
Over one fifth of these 260,000-plus bio-samples were taken by North Wales police, averaging just over 4,500 per year, not far-off 13 per day – and far more than this in recent years as the original rate increased tenfold from 620 in 1995 to 6,000 or so last year.
Should we be worried? The figures suggest the answer is emphatically “yes”, but what exactly to be worried about is less easy to ascertain.
Of the 55,694 DNA profiles North Wales Police has added to the database, 1,534 were from children aged under 16.
Are they all criminals or potentially so? Emphatically “no”. Anyone arrested and detained at a police station can have their DNA taken and recorded even if they are subsequently acquitted.
Young people, however, especially under-18s, make up a disproportionately large percentage of arrests. If they do go on to offend or re-offend they can be sure that the likelihood of their being apprehended is much greater than if their DNA had not been recorded.
There is no doubt that a sizeable number of repellent crimes have been solved thanks to the DNA database. Historic crimes can also now be reinvestigated and miscarriages of justice righted. It is a powerful tool and could be a deterrent too.
But as the percentage of the population being recorded inevitably grows, the government agenda remains obscure. We are approaching a state of affairs which would never have been countenanced politically, by stealth and default.
If the government wants a complete DNA database of every person in the country, sampled at birth or at the point of immigration, it should be honest about it, make the case and be prepared to have it tested by the electorate.
This will not happen because there is no need. Slowly but surely we will all find ourselves profiled for one reason or another, for tripping a speed camera, buying a few too many cans of beer in Calais or filing a late tax return.
Just as surely the database will one day be abused. We have been warned.