This article examines the establishment and development of constitutional justice in Lithuania, with particular focus on the role and jurisprudence of the Constitutional Court of the Republic of Lithuania (hereinafter—LCC). It considers two principal dimensions: the procedural expansion of the LCC’s competence to ensure the supremacy of the Constitution, and the substantive evolution of constitutional doctrine, particularly with regard to fundamental constitutional acts, constitutional traditions, genuine democracy, and the protection of human rights. Through the analysis of key rulings, the article illustrates how the LCC has shaped Lithuania’s constitutional identity, founded upon the principles of State independence, democracy and the inherent nature of human rights. In conclusion, by its jurisprudence, the LCC has not only strengthened the constitutional order of Lithuania but has also developed doctrinal safeguards against authoritarian rule and populism, thereby reaffirming the State’s enduring commitment to the rule of law and other democratic principles.