The Court recalled that it is a fundamental principle that no detention which is arbitrary can be compatible with Article 5 § 1 ECHR and the notion of ‘arbitrariness’ in Article 5 § 1 extends beyond lack of conformity with national law, so that a deprivation of liberty may be lawful in terms of domestic law but still arbitrary and thus contrary to the Convention. To avoid being branded as arbitrary, therefore, detention under Article 5 § 1 (f) must be carried out in good faith; it must be closely connected to the purpose of preventing unauthorised entry of the person to the country; the place and conditions of detention should be appropriate; and the length of the detention should not exceed that reasonably required for the purpose pursued.

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