There are cases where examinations are admitted, namely, before the coroner, and before magistrates in cases of felony. That appears to me to go rather in support of the general rule than in destruction of it. Every exception that can be accounted for is so much a confirmation of the rule that it has become a maxim, Exceptio probat regulam.
I won't say ours was a tough school, but we had our own coroner. We used to write essays like: What I'm going to be if I grow up.