To effectively control (or “monitor”) states’ respect for human rights one needs respect for human rights. Organizations, whether international organizations or private organizations (NGOs), must have some freedom to control, to engage in fact finding, to enter countries and move around, to investigate “in situ”, to denounce etc. Victims should have the freedom to speak out and to organize themselves in pressure groups. So we assume what we want to establish.
The more violations of human rights, the more difficult it is to monitor respect for human rights. The more oppressive the regime, the harder it is to establish the nature and severity of its crimes; and the harder it is to correct the situation.
However, we can establish that it is difficult to establish anything, which is proof enough of rights violations. Foreigners perhaps have somewhat more freedom than citizens of the countries in question. In the words of the French philosopher Cornelius Castoriadis:
How could one compose a free society unless free individuals are already available? And where could one find these individuals if they have not already been raised in freedom?