Why does C# allow you to 'throw null'?

Question

While writing some particularly complex exception handling code, someone asked, don\'t you need to make sure that your exception object isn\'t null? And I said, of course n

Answer 1

Trying to answer "..thankfully 'ex' is not null, but could it ever be?":

Since we arguably cannot throw exceptions that is null, a catch clause will also never have to catch an exception that is null. Thus, ex could never be null.

I see now that this question has in fact already been asked.