In Stage 3 of its review the Court has to examine if the contested interference can be held to be justified by objective and convincing reasons. One of the requirements for a restriction to be justifiable is the lawfulness requirement. The requirement has been given an autonomous and substantive reading by the Court, which entails that a restriction must have a basis in domestic law, the legal basis must be sufficiently accessible, the interference must be sufficiently foreseeable, and it must not be arbitrary. In addition, in particular in cases regarding surveillance, searches and the exercise of other discretionary powers, the Court has required that procedural safeguards must be offered. All these requirements are discussed in this chapter.

This chapter discusses how the European Court of Human Rights interprets and applies the European Convention on Human Rights. It examines the Court's approach to interpretation which stresses the Convention receives an effective, evolving and autonomous interpretation. The key principles involved in deciding whether a right has been appropriately limited or restricted are presented: legality or lawfulness, legitimate aim and proportionality. The margin of appreciation and positive obligations doctrines are explained.