Friday, February 29, 2008

DNA and Crime 2

In a police state, anything that makes the police more effective is a Good Thing.

We are being bombarded with various measures (actual and proposed) that apparently Lmake the police more effective. Longer detention-without-trial for terrorist suspects. CCTV evidence. And a national DNA database.

Proponents of these measures never fail to slip positive messages into the news media.

On the one hand, here's a terrible crime that was fortuitously solved many years later, *thanks to* the brilliant intervention of DNA scientists. On the other hand, here are some terrible crimes that may never be cleared up, *because* the relevant DNA wasn't recorded.

On the one hand, here is a wicked terrorist whom we were forced to release after a mere 28 days, although we *knew* he was plotting something terrible. On the other hand, here is another wicked terrorist, whom we were able to prosecute *because* the evidence just happened to emerge after a mere 45 days of investigation.

Opponents of these measures sometimes argue that they are ineffective or inaccurate. It is implausible to believe that evidence will suddenly appear after 28 days that was not available before. They say they will only agree to this measure if it can be shown that it sometimes works.

Other opponents argue that they are disproportionate. They do not deny that they may possibly work in a few cases, but claim that the benefits are grossly outweighed by the illiberal side-effects.

The problem with both of these lines of argument is that they are vulnerable to constructed refutation. Detection can be attributed to DNA for crimes that might possibly have been solved by other means. Suspected terrorists can be detained for the maximum permitted period, not just because the investigators are under less pressure to find evidence more quickly, but also because the investigators need to demonstrate that the currently permitted maximum is barely enough. Under certain conditions, the statistics could start to look very favourable, enough to overcome the "disproportionate" argument.

And the supporters of these measures have a further argument up their sleeve - the hypothetical deterrent effect. Imagine how many more crimes might have been perpetrated: would-be criminals who saw the cameras, or remembered the DNA held hostage in the police database, and decided to stay home and watch Big Brother instead. Imagine how many more people might have attempted to smuggle dangerous chemicals or stiletto heels onto aeroplanes, if it had not been for the constant vigilance of dedicated security screeners.

My point is this. Opponents of some specific measure may declare that the measure is unacceptable or counter-productive in a civilized society, may declare that the measure could only be accepted if such-and-such facts could be produced. And they may believe that this opposition is fairly solid, because these facts are extremely unlikely.

But what if the advocates of these measures are able to influence the facts? ...

Of course, I am not saying we are in a police state today. I am not even saying that specific measures would turn our country into a police state. All I am saying is that it is possible to see how repeated application of certain lines of argument could result in a police state.

Update


Here's some evidence to support my conjecture:

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