It is far from clear to me that lockdowns to prevent a virus from spreading are ethically justified. The more I think about it, the more unjust they strike me.

For instance, imagine Jane and Bill want to meet. And Jane and Bill know full well that were they to meet, they will subsequently die as a result. Nevertheless, they still want to. That is, they value more highly meeting one another than continuing to live.

Okay - am I entitled to stop them meeting? I think it is intuitively obvious that I am not. Who am I to do so? They are free agents, and they understand the consequences of their actions at least as well as I do, and so it would be, well, somewhat outrageous of me to stop them meeting. I mean, their act strikes me as quite unwise. It may even, perhaps, be unethical (for perhaps it is unethical to do something you know will kill you, exceptional circumstances aside). But even so, I do not seem justified in preventing them from meeting. And nor do you.

We recognize this in other contexts, for patients are allowed to refuse treatment, aren't they, even if their refusal will result in their deaths. That's their right. So we have a right to do things with our lives, including things we know will result in their termination, if we want to.

Now let's imagine that rather than knowing they will die if they meet, they just know that there is a small chance they will. Maybe a chance of, say, 100:1. Okay, well surely if I am not justified in preventing them from meeting when it was certain they'd both die and they knew this, I am surely not justified in preventing them from meeting when there is just a relatively small risk that they'll die. That seems clear.

Well, isn't that the situation we're all in with the pandemic? We know that if we associate with others, there's a risk we'll get the virus or, if we unknowingly have it already, pass it on to others. But, well, so long as we all know this, surely no one has the right to stop us associating if we want to?

Things would be different if you knew that you had the virus and knew that others did not know this. For now you are knowingly exposing others to a risk that they did not know they'd be exposed to. But that's not the situation. If the situation is that there is a population of people who know that there is just a risk that they'll die by associating - but a mutual risk - then it seems to me quite unjust to prevent such people from associating if they so wish.

Nothing stops individuals from locking themselves down if they so wish. If you judge that the risk of getting the virus is just too great to justify associating with others, then so be it: no one is making you associate with others, so just don't. Yes, it'll cost you your job or your business. But then you clearly value more highly not running the risk of getting a virus than you do your job. And it would be quite unjust for anyone to force you to go to work or force you to keep running your business, wouldn't it?
Well, the reverse is surely true too. if it would be wrong to force you to go to work if you do not want to, surely it is wrong to force you not to if you want to?

It seems to me, then, that lockdowns are unjust. Individuals can make their own judgements about risks and benefits. And it is not for others to impose a one-size fits all judgement about the matter on a population as a whole. So long as we're all innocent threats to one another, we should be free to associate (if, that is, we want to).