This paper aims to analyze the instrument of an extraordinary complaint, its legal character and fundamental function considering the plans of its elimination from the justice system. It points out the role of this complaint as a means of protection against the breaches of constitutional rights and freedoms that may arise when a court judgement is issued. It indicates the need for a legal instrument which can be used to explore the constitutionality (compliance with the Constitution of Poland) of the acts of law (judgements, decisions and court orders). Without it, there is a gap in the legal system as regards the protection of constitutional rights. It is claimed that the possibility of dispersed control over the constitutionality of the law application in individual cases is desirable. The paper also includes proposals of amendments of the instrument of an extraordinary complaint. These involve the extension of the list of entities authorized to file it, the narrowing down of the grounds for the complaint, shorter deadlines for its filing or no need of jurors. They provide an opportunity for a discussion as to whether the extraordinary complaint should be amended, restricted in terms of the grounds for it or entirely eliminated from the justice system.