Political parties' autonomy is a constitutionally protected value, however the scope of its protection cannot ignore the political reality, particularly the constant erosion of traditional functions of political parties. Currently, it seems that internal democracy has become an absolute prerequisite for the performance by political groups of their role in conformity with the Constitution. Internal party democracy might be considered to be as important for the functioning of political parties as party autonomy. Therefore, the legislature should adopt laws providing for guarantees of rights of party members, governing - inter alia - the procedure in disciplinary matters and allowing for recourse to the court in such cases. The principle of party autonomy does not justify leaving the issue of expelling a party member within the scope of internal party regulations (statutes), as it would lead to arbitrariness on the part of political groups. The voluntary nature of association in political parties implies an obligation to provide citizens with legal recourse against arbitrary deprivation of rights ensuing from party membership. The possibility to contest substantial internal party decisions before the courts by party members should be supported. It is also well considering that decisions of party authorities be made public, e.g. on the Internet web-pages of a political group. Public access to such documents would facilitate wider debate and prevent, even partly, the arbitrary practices of party leaders.