If he was sincere, he might doubtless earn the pardon which he so much desired.

But was he sincere?
Had he not been just as loud in professions of loyalty on the very eve of his crime?
It was necessary to put him to the test.

Several tests were applied by Sackville and Lloyd.

Marlborough was required to furnish full information touching the strength and the distribution of all the divisions of the English army; and he complied.

He was required to disclose the whole plan of the approaching campaign; and he did so.
The Jacobite leaders watched carefully for inaccuracies in his reports, but could find none.