Extradition — Capital offences — Offence carrying death penalty in requesting State but not in requested State — European Convention on Extradition, 1957, Article 11 — Requirement for requesting State to give assurance that death penalty will not be carried out — Nature of assurance required — Whether courts or Executive in requested State responsible for determining adequacy of assurance given

States — Conduct of foreign relations by Executive — Basic Law of Federal Republic of Germany, Article 32(1) — Extradition request — Obligation of requested State to seek assurance that death penalty would not be imposed — Whether assessment of adequacy of such assurance a matter for the courts or the Executive — Duty of Executive to provide courts with information concerning prevailing situation in requesting State — The law of the Federal Republic of Germany