"Everybody, guilty or innocent, should expect their DNA to be on file for the absolutely rigorously restricted purpose of crime detection and prevention -- and no other purpose."
"For no other purpose". Why, are there other purposes that the judge knows about?
As it turns out, we already know what the British Government does with DNA databases: it sells them to large private companies which then run amok figuring out who they can tell. Admittedly, the article was from some obscure paper called the Guardian, that the Senior Judge might not have read.
Why else might we object to it? Well, as it turns out, it encourages the already poorly run police forces and prosecutors to take shortcuts:
In fact, we have an example, easily findable, showing that DNA analysis can be spectacularly wrong:
What is also to be expected from a thorough trawl of this mammoth database would be around 100 billion attempts to match crime scenes with potential suspects, resulting in over two thousand false cold hits. More if the labs are capable of making mistakes.
The first false cold hit from a database trawl to be recognised in the UK was in 1999, though it did not become public knowledge until the following year after a UK forensic scientist addressed the USDOJ Commission on the Future of DNA Evidence.
A man with advanced Parkinsons disease who could not drive an automobile or dress himself unaided was linked to a burglary which had occured 200 miles from his home. In spite of protestations of innocence and alibi evidence police arrested him because the DNA profiles matched and 'so it had to be him'. It was several months before 10-point DNA tests were done on samples from the suspect and the crime scene. The results exonerated him.
He gained his freedom and a brief note from the prosecutor saying that charges were being dropped because "there was not enough evidence to provide a realistic chance of conviction". He still awaits an official apology. Or even an admission of error.
Read the article carefully: you'll know why it's a good idea to look for actual evidence, and treat DNA as confirmatory, rather than probative.
Fortunately, the article quoting this lunatic senior judge also contains quotes from others indicating that even though they don't know why there is a problem, they sense there might be. I must be the only one who reads the Guardian out there, or who has a memory, or they would start at the same place I did: what is government becomes corporate.