He knew that this final plea was unsound, but he did not see how to contest it.

So he came back to fact, which was easier for him.
"How am I to know, monsieur, what would be the wishes of those who have entrusted me with my position?
You are placed in authority by some means here, in your own country, but against it.

That much you have proved to me, by papers.

But your credentials are general only.

They do not apply to this especial case.