The Home Office has issued a new code of practice pursuant to the Regulation of Investigatory Powers Act 2000 section 71. The Code of Practice relates to the powers and duties conferred or imposed under the Data Retention and Investigatory Powers Act 2014 part 1 and the Data Retention Regulations 2014. The Code of Practice provides details of the procedures to be followed when communications data is retained under the aforementioned provisions.

https://www.gov.uk/government/uploads/system/uploads/ attachment_data/file/426249/Retention_of_Communications_Data_ Code_of_Practice_March_2015.pdf