“However, if an entity can pass the test by remaining silent, this cannot be seen as an indication it is a thinking entity, otherwise objects such as stones or rocks, which clearly do not think, could pass the test. Therefore, we must conclude that ‘taking the Fifth’ fleshes out a serious flaw in the Turing test.”
Turing did not explicitly state that the Turing test could be used as a measure of intelligence, or any other human quality.
Every element of this assumption has been questioned: the reliability of the interrogator's judgement, the value of comparing only behaviour and the value of comparing the machine with a human
The susceptibility to insults, the temptation to lie or, simply, a high frequency of typing mistakes. If a machine cannot imitate these unintelligent behaviours in detail it fails the test.