A child is in mortal danger. This man can tell you where he is, but won't talk. What would you do? Since the 17th century, Britain has been clear that it is wrong even to threaten suspects with torture or beatings. Nick Cohen asks if a German case could make us change our minds

Every now and again, practice lives up to theory. Although there's yet to be an example of a supporter of free speech going to the West End and being confronted [...]