The Supreme Court is a special authority of the judicial power that executes defined tasks, not only the essential ones, arising from the Constitution, concerning an exercise the administration of justice and supervision of common and military courts regarding judgments but also a number of others included in the lower-level acts. The article analyzes one of its statutory tasks consisting in issuing opinions on draft laws and other normative acts on the basis of which courts adjudicate and operate, as well as other draft laws to the extent that they affect matters within the jurisdiction of the Supreme Court. The purpose of this study is to consider the task assigned to the Supreme Court and in connection with this answer the question whether the principle of cooperation of powers expressed in the preamble of the Constitution is reflected in the legislative process, especially when the subject of legislative work are fundamental legal acts concerning the functioning of the judiciary.