Lord Sumption:

I can only answer that question in the context of the law of the United Kingdom. I am not an expert but I believe the basic principles are very similar in Ireland. The best way to challenge that type of problem would be to claim that a response is irrational. My view is that, as a matter of public law, the Government is entitled to a very wide margin of judgment in the area of rationality and a claimant would need a very extreme and obvious case indeed for a challenge to be successful. Having said that, looking at administration from the Government's point of view, there is obviously a lot to be said for fine-tuning the regional impacts of these measures as much as possible. Most countries in Europe have done this in one way or another. In the United Kingdom, we now only impose lockdowns in specific areas which have seen higher levels of infection. France has a system of green, red and orange areas. This system is under the control of departmental prefects and it seemed to work very well. For instance, it meant that at the height of the pandemic the scale of restrictions in Paris, where the infection rate was highest, was much greater than in Moselle or Dordogne, where the figures were much more favourable.

That seems to be a sensible way of doing it. Ultimately, this is a matter of political and administrative judgment. It is not easy to deal with it by law, which is essentially a blunt instrument. Of course, one has to have the power but, ultimately, the decisive factor is going to be the element of clinical, epidemiological and political judgment.