“In particular, the national legislation must make provision for the data to be retained within the European Union and for the irreversible destruction of the data at the end of the data retention period …”
“Likewise, the competent national authorities to whom access to the retained data has been granted must notify the persons affected, under the applicable national procedures, as soon as that notification is no longer liable to jeopardise the investigations being undertaken by those authorities. That notification is, in fact, necessary to enable the persons affected to exercise, inter alia, their right to a legal remedy, expressly provided for in Article 15(2) of Directive 2002/58, read together with Article 22 of Directive 95/46, where their rights have been infringed …”
“As regards the setting of limits on such a measure with respect to the public and the situations which may potentially be affected, the national legislation must be based on objective evidence which makes it possible to identify a public whose data is likely to reveal a link, at least an indirect one, with serious criminal offences, and to contribute in one way or another to fighting serious crime or to preventing a serious risk to public security. Such limits may be set by using a geographical criterion where the competent national authorities consider, on the basis of objective evidence, that there exists, in one or more geographical areas, a high risk of preparation for or commission of such offences.”