The study indicated Fundamental guarantees of rights and liberties come in different forms, some of which are realistic and attempt to improve the state of affairs so that people can enjoy their rights and freedoms. The constitution is the pinnacle of the legislative pyramid and cannot be disregarded. When passing new laws, lawmakers must consider the constitution's provisions. As a result, these laws' constitutionality must be scrutinized. The researcher will focus on judicial oversight, particularly concerning the methods of filling constitutional cases. He will also discuss the direct lawsuits, Based on the foregoing, the study reached several results, the most important of which are: establishing a constitutional court tasked with overseeing the constitutionality of laws is, in essence, a success that merits praise, as the court's existence is regarded as a guarantee of the rights and liberties that the constitution comes with.