I will argue that physicians have an ethical obligation to justify their conscientious objection and the most reliable interpretation of the Polish legal framework claims that conscientious objection is permissible only when the justification shows the genuineness of the judgment of conscience that is not based on false beliefs and arises from a moral norm that has a high rank. I will demonstrate that the dogma accepted in the Polish doctrine that the reasons that lie behind conscientious objection in medicine (...) cannot be evaluated or controlled by anyone is based either on a mistaken interpretation of the Constitution or on the unreliable concept of conscience. I will refer to the legal regulations concerning military refusals that require from objectors to reveal and justify their views. Finally, I will demonstrate why conscientious objection under uncertainty does not deserve acceptance, because it is based on a specific version of the precautionary principle. (shrink)