What have DNA database objectors got to hide?

Nick Freeman writes in the Manchester Evening News:

How many millions of hard earned tax payers’ money will be spent trying to catch Jo Yeates’s killer?

Hopefully nowhere near as many as the millions that were squandered in apprehending the wrong man in the Rachel Nickell murder case, before the real killer was finally caught – and only after he had killed again.

In the Nickell case, the police finally got their man after trapping him with a scrap of DNA. And we can only pray that the savage murderer who took the life of the young landscape architect from Bristol will be swiftly snared in the same way – but what if the police don’t have his DNA?

Hasn’t the time now come for everyone’s DNA to be stored on a national register – rather than, as is the case at present, just the samples taken from criminals or suspects?

In plain and simple terms, that means every person living in this country should, by law, be required to give a sample which would then be held on a database accessed only by law enforcement authorities.

He concludes:

And if you object? Well, I’m just wondering what you’ve got to hide.