That is an unreasonable test. When we are employing or appointing someone to a sensitive position we have to use our own character assessment. We compensate by alloting the task to an hopefully diverse interview panel. Such panels are not usually required to be able to demonstrate that their assessment is true.

Anyway, Clinton gave his reason for stating that he did not have sex with that woman : oral sex does not count_. Quad est demonstrandum, because for a President representing the USA to the world, it certainly does count.