privacy interests in the data sought or the place where it is located, the more formal and time-consuming the investigative and international co-operation procedures become. Compliance with human rights safeguards may take more time when the request originates in a different country. 2.6 The Group noted the importance of provisions whereby data could be identified or 'frozen' by the requested state and then released to the requesting state once the appropriate safeguards had been applied. The Group also noted the expanding use of ‘24/7’ networks whereby investigators in one state could obtain immediate assistance in another to trace and identify target data, assess its nature and ensure that the appropriate procedures were followed as efficiently as possible. The Group further noted that under-estimation of privacy interests could compromise basic human rights protections and the admissibility of the evidence in one or both of the states involved, while on the other hand, over-estimation of privacy interests could unnecessarily delay investigations by the use of formal channels when they were not needed. 2.7 There are many informal networks within the Commonwealth, such as the Commonwealth Network of Contact Persons. The Commonwealth context, with a shared legal tradition and a common approach to many matters of administration and agency procedures, makes those networks especially effective; within them, there is an easy understanding of requests for help. Formal instruments for co-operation 2.8 Where more formal procedures are necessary, the requirements for co-operation may be set out in instruments of different types. These include memoranda of understanding between specialist agencies; obligations of co-operation derived from common membership of a regional organisation; instruments such as the Schemes adopted by Law Ministers which have a force that falls short of a treaty; Model Laws that have been adopted by both states concerned; and bilateral treaties and multilateral treaties open to states within a particular region or of potentially global effect. 2.9 In some cases, several modes of proceeding may be available. This is recognised in the text of the Budapest Convention, article 23 of which sets out general principles relating to international co-operation: The Parties shall co-operate with each other, in accordance with the provisions of this chapter, and through the application of relevant international instruments on international co-operation in criminal matters, arrangements agreed on the basis of uniform or reciprocal legislation, and domestic laws, to the widest extent possible for the purposes of investigations or proceedings concerning criminal offences related to computer systems and data, or for the collection of evidence in electronic form of a criminal offence. Criteria for the selection of instruments 2.10 Although ad hoc arrangements may be very useful, a standing and binding arrangement that can be invoked as required is a very desirable part of the armoury of a state engaged in combating cybercrime. It is possible to set out some criteria to be used in assessing the various instruments that a state may choose to adopt, criteria also relevant to the Group’s task: 26