This article is a contribution to the biography of Professor Andrzej Kabat – a prose-cutor, legal counsel, judge of the highest courts of the Republic of Poland, and a long-time academic teacher. The study discusses selected jurisprudential achieve-ments of Professor Andrzej Kabat from the period when he held the office of a judge of the Constitutional Tribunal and the Supreme Administrative Court. Moreover, there are also references to his research on the institution of questions of law sub-mitted to the Constitutional Tribunal, which is regarded as pioneering in the science of law, despite the fundamental changes in the political system. What marks the discussed output of Professor Kabat is both the relevance of his ideas and the great significance for the practice of application of the law.