Sher and others v. the United Kingdom, No. 5201/11, ECtHR (Fourth Section), 20 October 2015

Respect for private life and right to receive adequate information concerning specific allegations and arrest warrants.

Art. 5 ECHR
Art. 6 ECHR

A deprivation of liberty is permitted where there is a reasonable suspicion that a person has committed an offence. However, terrorist crime falls into a special category. Because of the attendant risk of loss of life and human suffering, the police are obliged to act with the utmost urgency in following up all information, including information from secret sources. Further, the police may frequently have to arrest a suspected terrorist on the basis of information which is reliable but which cannot, without putting in jeopardy the source of the information, be revealed to the suspect or produced in court. Article 5 § 1 (c) of the Convention should not be applied in such a manner as to put disproportionate difficulties in the way of the police authorities in taking effective measures to counter organised terrorism. Pursuant to Article 5 § 4, the authorities must disclose adequate information to enable the applicant to know the nature of the allegations against him and have the opportunity to lead evidence to refute them. However, contracting States cannot be asked to establish the reasonableness of the suspicion grounding the arrest of a suspected terrorist by disclosing the confidential sources of supporting information or even facts which would be susceptible of indicating such sources or their identity.