PITCOM Journal Spring 1999 - Electronic Commerce and Public Policy: The Law Enforcement view

The devastating effects of irretrievable encryption

Mark Castell, of the National Criminal Intelligence Service, argues for Key Escrow

Electronic commerce and the technology that accompanies it, including encryption, are increasingly parts of UK life. The National Criminal Intelligence Service (NCIS) in leading law enforcement's response to the Government White Paper "Building Confidence in Electronic Commerce", recognises both the benefits offered by the lawful use of encryption. and the dangers posed by its criminal use. Therefore, It accepts the need for a solution that meets the needs of all interested parties.

The benefits of Encryption

Encryption undoubtedly has positive benefits in many areas, including law enforcement. Payment systems and cash dispensers rely on it to secure the integrity of transactions. Similarly it will also help to prevent crime on the Internet - it will be increasingly difficult to defraud companies and individuals. Obviously encryption also plays a role in protecting intellectual property in both the public and private sectors.

NCIS has some major concerns about the ability of law enforcement to gain access to the plain text version of material that has been encrypted. As our response to the Department of Trade. and Industry's document states: "In our view the licensing proposals do not go far enough to ensure that suppliers and users of cryptographic products keep material that permits access to encrypted data."

Opportunities for criminals

The benefits of encryption to society at large need to be balanced by the opportunities presented to the criminal fraternity. Criminals use technology as any other business does - criminal organisations of the type targeted by the National Criminal Intelligence Service are on a par with large corporations and use the tools best suited to carry out their business effectively. Criminals have exploited encryption (and will continue to do so) in their constant bid to out-manoeuvre law enforcement.

Whilst it is true that the use of encryption is not widespread at the present time, it has already presented considerable problems In areas of serious and organised crime such as drug trafficking, paedophilia and terrorism. The current situation simply reflects the penetration of encryption products into the marketplace: As criminals become more IT literate and use of encryption throughout society increases, so will its ability to severely hamper law enforcement at all levels of fighting crime.

What solutions are there for law enforcement In this fight against criminal use of encryption NCIS supports the government's three track approach, which advocates the updating of existing law enforcement powers; the encouraging of third party access; and co-operation between Government and industry to mitigate the effects of the criminal use of encryption.

No New Powers

Firstly it must be clear that law enforcement are not asking for any new powers, merely that existing powers be adapted to allow law enforcement to maintain its effectiveness in protecting public safety. We are asking that whereas in the past any lawfully obtained material was likely to be comprehensible, the widespread use of encryption would mean that increasingly it would be indecipherable. One example of this involves paedophilia, an area in which NCIS is already aware of increasing use of encryption: if indecent pictures of a child were stored as photographs within a safe, physical means could be used to gain access to this material or the key could be demanded. An updating of present powers would allow law enforcement to gain the same access if the pictures were encrypted.

Third Party Access

There is the old observation that if the only retrievable part of a crashed aircraft is the flight recorder (the 'black box'), then why not make the whole aeroplane from the same material. If houses were built of this 'unbreakable material', this would mean that the police could not force entry if they knew that a man were inside murdering his wife. In such a world, would it be unreasonable for the Government to require house builders to keep a spare copy of the front door key, or to lodge it with the court?

Encryption presents similar problems: where data could previously have been read, it would now be 'uncrackable'. The 'black box and builders' analogy analogy is far removed from the more simplistic and inaccurate myth being perpetrated, that the key escrow is the same as the police asking for everyone to hand in their house-keys to the local police station in case a search is required when the occupants are away.

The major issue to be tackled is not access to decryption keys, but whether access to decrypted material is available when lawfully required. NCIS's favoured approach would be a mandatory licensing system with key escrow (the holding of all decryption keys by a secure third party) as a licensing condition. This trusted third party could then be approached by law enforcement for the keys, once the statutory safeguards had been satisfied. Such a system would allow law enforcement to access the material in real time without the need to waste time in cracking the encryption.

Government/Industry Co-operation

In the current political environment, any policy proposing e mandatory linkage between licensing and key escrow is unlikely to succeed. The industry lobby has argued strongly that this would undermine the very trust that encryption should bring. There are sound business reasons for designing and using systems that permit third party access to data. Having moved away from a mandatory requirement, the Government is now reliant on the co-operation of industry in order to protect public safety. Encouraging third party access is one way that industry could co-operate.

Two of the benefits of the favoured key escrow system are cost effective and timely access. The history of the efforts at Bletchley Park (Station X) to crack the German Enigma Cipher during the second World War demonstrate that it is sometimes possible to crack encryption. However it also teaches us that it required a great deal of effort and sometimes the results do not arrive in time to avert disaster. Advancements in technology are continuously producing encryption that is increasingly difficult - if not impossible. to crack. The availability of decryption keys would provide a more cost-effective solution to decrypting lawfully obtained material.

Time is the key in fighting crime

Time is always pertinent in the fight against crime. Criminals do not wait for law enforcement to finish their preparation before committing an offence - especially not at the serious end of the criminal spectrum. Timely access to information is therefore vital. Certain techniques provide this, such as Interception of communications. This information, analysed and contextualised, is the intelligence upon which effective modern day policing relies. Time delays caused by having to crack en encrypted message means that the material gained is of little use to intelligence officers or an operational team.

No resources for snooping

The limit on available resources is also powerful in countering a common civil liberties' position that law enforcement would utilise the new extension of powers to snoop into the general public's life. Notwithstanding the stringent safeguards previously discussed, resources are so limited and therefore necessarily focused on criminal activity, that there is no spare capacity to 'snoop' on innocent members of the public.

Electronic commerce obviously, by its very nature expands outside national boundaries. Equally criminals are not renowned for their desire to respect national boundaries. The best solution to criminal use of encryption must therefore be global. In a global market, only a global solution will ensure that there are no ghettos for the criminal use of encryption.

NCIS would therefore encourage Her Majesty's Government to do all that it can in the international arena to promote co-operation between nations on the issue of law enforcement access to decrypted material. The need for a global solution should, not though, prevent the United Kingdom from leading the way or simply being the first. Even if other countries do not follow, does not mean that the opportunity to legislate in the UK should be missed. Criminals, like many others, will often use the quickest and most available tools.

The effect of irretrievable encryption

To conclude, the value of current access to material that could be encrypted - emails and telecommunications -  should not be underestimated in the fight against serious and organised crime. The effect of material being made irretrievable through encryption could potentially be devastating .

In 1998/97 material gained through interception lead to the arrest of 1200 people, the seizure of 700 million worth of cash and property and 450 firearms, as well as three tonnes of class A drugs. This would be enough for 6 wraps of heroin for each child of secondary school age.

This material, criminals and finance - and much more as encryption increases - could potentially all be unreachable if law enforcement is prevented from accessing material in a usable format.

Mark Castell is an officer at the National Criminal Intelligence Service dealing with encryption policy.