It can argued courts do make laws in legal field. It can be argued and has been argued, courts make laws by interpreting a law. Courts can and have interpreted laws. This in return can change the substance of the law or how is it enacted. Also, courts can make a decision about the validity of the law based on the constitution. The U.S legal system is common law which allows its judiciary branch to interpret laws. The question you have asked can go both ways.
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