November 24, 2014 | Jim Killock

Blanket data retention does not come in “good” and “bad” forms

Yesterday’s announcement that mobile phone providers will be obliged to keep records of their customers IP addresses (and port numbers) came as no surprise. But what we need to remember is that all data retention should be subject to the same principles, conveniently outlined by the Court of Justice of the European Union.


These principles include that data retention should be targeted against a specific threat, confined by criteria such as a specific time or place. The new proposal, while being consistent with existing arrangements for ISPs in the UK, is another proposal for blanket retention beyond what is needed for business purposes.

In any case, this is a rather backward proposal, dealing with a problem that exists because the mobile companies continue to rely on out of date technology. To take a moment to explain: the Internet is famously running out of addresses (numbers that identify a point on the Internet – Internet Protocol version 4 (IPv4) addresses).

To deal with the lack of address space, mobile companies use a technology called "Network Address Translation" or NAT, which allows several devices to share the same IP address. Most people use this at home to allow two or three computers to use the ADSL or cable connection, However the mobile companies do this at a far greater scale called "Carrier Grade NAT" — and there will be hundreds of different people using the same IP address.

However, all of this technology needs replacing. It limits the usefulness of Internet connections, particularly reducing our ability to use peer-to-peer technologies. The government ought to be asking providers to invest in IPv6, rather than upgrading their current, limited technology, just for the purposes of further logging our movements.

Proposals for surveillance need to be justified not just because of the increased convenience for police, but on the basis that they do not intrude more than is necessary for specific criminal enforcement. This does not mean that all events should be logged and tracked at all times in order that police can always use a source of evidence for investigations. Yet rhetorically we know this is where the surveillance lobby has already arrived. As Jack Straw asked, how can data retention be limited on the basis of suspicion: the police are not “clairvoyant”, they cannot know which of us will need to be investigated in the future.

The problem with Straw’s argument is that if you accept it, then it is impossible argue against the destruction of any data, ever. Any of it might be useful to the police, so all of it should be kept. Maybe we should be obliged to retain our hard drives forever.

The choice is always between blanket, pervasive and excessively intrusive surveillance, where everything is collected, and proportionate, targeted collection where there is a possibility that sometimes something might go missing. However, in an age where data is generated at multiple points, by increasing numbers of services and devices, a lack of digital evidence should be the exception rather than the rule. Claims of data going missing should be treated with caution.

The important point in relation to new mobile IP data retention is that it suffers from the same problems as previous proposals. It is unbalanced and lacks any serious restraint. In order to get the principles right we need to examine the whole of the data retention question. Theresa May denied us that opportunity only months ago. Now she is seeking to press ahead, again with agreement of her coalition partners, who also need the opportunity to look at this question in the round.

Her calls for the Snoopers’ Charter, and building the surveillance regime piecemeal, has the effect of eroding the principle behind defining the basis of proportionate measures to retain data, and surreptitiously signing up Parliament to the idea that blanket collection is not necessarily a problem. MPs can place lines in the sand based on their sense of public concern, rather than the principles. Once the principle that blanket data retention is fully accepted, resistance to the Snoopers’ Charter will weaken, and MPs will turn to oversight as sufficient protection. 

That is why we need a full debate about the whole question of data retention, in the light of the CJEU judgment. The effects of that judgment on UK law are not yet fully understood, but David Davis MP and Tom Watson MP, as well as ORG, are seeking to challenge the existing data retention regime.