The judiciary plays a critical role in upholding the constitution by interpreting laws and ensuring they align with constitutional principles. Courts have the authority to review legislation and executive actions, protecting individual rights and maintaining the rule of law. Through the process of judicial review, the judiciary can strike down laws deemed unconstitutional, serving as a check on governmental power. This function is vital for maintaining a balance of power among the branches of government and ensuring that democratic ideals are preserved and reinforced within the legal framework of a society.