The Privacy of Thoughts

Imagine a world where thoughts could be read irrespective of whether the victim wanted them read or not. What a horrible shift in the balance of power. Reminds me of the Second Foundation of Isaac Asimov.

Imagine now that thoughts could not only be read but could also be influenced. Would the experimentation begin on animals and the comatose or would it happen on normal people? How would the 'subjects' be selected?

At the beginning, would there be any laws governing how this works or would it be at the arbitrary whim of the inventor? A 'god', a megalomaniac who decides what is right and what is wrong and what punishment to mete out. Imagine some such device in the hands of Mengele or one of his descendants...