Human rights — Right to respect for private life — Use of secret information in assessing suitability for employment in post of importance for national security — Whether job applicant entitled to release of secret information — Balance between State’s national security interest and individual interest — Margin of appreciation — Freedom to express opinion — Freedom to receive information — Whether refusal to release secret information to individual who is subject of that information constituting interference — Right to effective remedy before national authority — Whether referring to investigative and decision making body independent of executive — European Convention on Human Rights, 1950, Articles 8, 10 and 13