There are some Catholics who believe that the present laws on abortion must be upheld because 'law is law'. They believe in legal positivism which holds that a law is valid because it is successfully promulgated and enforced.
History has shown this is not the case. Doctors were authorised by laws under the Third Reich in Germany to kill prisoners in medical experiments. Later, after the war, they claimed in their defence that the law at the time authorised or allowed them to do those experiments.
This defence was rejected by the courts who declared that positive legislative acts lose their obligatory power if they violate natural law. People are obligated to ignore those unjust laws and to uphold true justice.
Government authorised abortion clinics are therefore unjust in that, even though allowed by recent law, that law does not produce any legitimate legal effect. Future governments would be just in setting up courts to prosecute present-day abortionists for crimes against humanity. They could not use as their defence that 'law is law'.
To put it in the terms of St Thomas Aquinas, 'An unjust law is a human law that is not rooted in eternal law and natural law'.
Rosa Parks refused to give up her seat on a bus in the American South in 1955. Natural law supported her stand against an unjust segregationist law. This is an example often cited by the left/liberals.
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