Not quite sure of the difference between unimpeded executive power and tyranny
No, really.
'"The court, whose duty it is to secure an individual's liberty from unauthorized and illegal Executive confinement, cannot now tell a prisoner that he must beg leave of the executive's grace before the court will involve itself. This very notion offends the separation-of-powers principles and our constitutional scheme."'
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Judge slams military efforts to limit GITMO detainee access to lawyers
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The only difference is the abuse of power. Since that's highly subjective, there is no difference, really.