National’s idea to permit the DNA sampling of anyone arrested for an alleged offence carrying a term of imprisonment opens a new can of dangerous worms.

It appears to overlook the fact that, under current law, everyone is assumed to be innocent until proven guilty. So the mere fact of being arrested, under National’s plan, damages that principle – because it implies some element of guilt before this has been proved in court.

We recently had another sly instance of the law being indirectly turned on its head when a judge refused bail for a person charged with illegal possession of firearms on the grounds (as reported by Radio New Zealand National) that “he might offend again”.

Beg your pardon, m’lud? What sort of re-offence? The guy is probably years away from standing trial, and at this stage he has to be presumed innocent of anything, despite being a suspect of doing something. And he’s hardly likely to visit the friendly neighbourhood illegal arms dealer in the near future…

Let’s also not forget that while a group of people are banged up in jail on suspicion of illegal possession of firearms, Molotov cocktails and perhaps something slightly worse, we have people actually charged with murder walking about on bail – in some cases, waiting up to two years for their trials.

National’s fuzzy idea wouldn’t just cover suspected killers, muggers, rapists or burglars. It would probably ensnare anyone from a car driver to a dog owner, under the right circumstances.

Some would say that if you’ve done nothing wrong, what’s wrong with having your DNA recorded?

To which the obvious answer is: in that case, everyone in New Zealand should give a DNA sample. You might be completely innocent today, but that doesn’t mean you won’t do something horrific next year, and nowadays DNA’s often the key to solving the crime.

Forensic scientists say that it is virtually impossible to leave the scene of a crime without leaving some trace of your DNA behind.

So let’s not pussy-foot about. Make it compulsory to supply your fingerprints and dental records to the police database, too… No one blinks an eye about civil liberties when prints or dental records are used to identify corpses. What’s the difference?

National’s half-baked policy will please no one but the clever criminal. Even if we accept their half-way house, it still means that you have to be thought to have done something wrong before your DNA goes on record – surely a case of the horse having already bolted?

The policy is certain to generate a howl of anguish from the usual suspects, as well as all sorts of rubbish about Human Rights.

If this is the best National can come up with on law and order, we can hardly expect a bold new direction from them on the other important issues that Labour also finds too hot to handle.

Orwellian or not, the only satisfactory way to improve the rate of crime resolution is to make DNA sampling compulsory for everyone. One day, we predict, it will be as normal as an IRD number.