A close friend is a brilliant legal scholar and an expert on constitutional law (obviously not from the UK, since they haven't had a constitution in a long time).

We debated the legalities of torture once, and I remember asking him "What if someone poisoned the water supply to a major city, and you have to find out which one?" It's a bit of a silly question, but simplified thought experiments can be interesting.

He answered something ala "The law is meant to operate within certain boundaries of human behavior. Once behavior goes outside of those norms, the law is no longer a meaningful guideline". It was an unexpected answer, to say the least - but I found it interesting.

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