An interesting article on CNET describes U.K. police’s attempts to seize encryption keys used by suspects to encrypt data which may help the police solve the crimes. According to a "senior police officer,"

Because British law enforcement officers don’t have the authority to seize encryption keys, an increasing number of criminals are able to evade justice.
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There are more than 200 PCs sitting in property cupboards which contain encrypted data, for which we have considerable evidence that they contain data that relates to a serious crime. Not one of those suspects has claimed that the files are business-related, and in many cases, the names of the files indicate that they are important to our investigations.

A controversy was stirred earlier this summer when the British government announced that it planned to activate Part 3 of the Regulations of Investigatory Powers (RIP) Act, which allows the police, in some circumstances, to demand an encryption key from a suspect.  Under Part 3 of the RIP Act, if  the police suspected someone had encrypted incriminating data, officers could issue an order under Section 49 of the Act, ordering the suspect to hand over the key. Failure to do so could lead to a prosecution under Section 53 of the Act.

Critics of the Act point out that the law is dangerous, is badly written, and cannot be properly implemented. For example, under the Act, defendants could be prosecuted for simply losing an encryption key. Furthermore, critics point that the code of practice lacks clear powers against use of the RIP Act to obtain private data. Because of clear procedures, businesses may take their encryption keys out of U.K. jurisdiction so that their secret business information is not in jeopardy of being revealed by an overzealous prosecutor or one with an improper agenda.

On the other hand, the British Home Office has defended law enforcement’s position that the time is right to activate Part 3 of the Act because law enforcement are finding that an increasing number of their investigations are thwarted by encryption. It is easy for police officers to point to cases where child abuse victims remain unidentified because a suspect has encrypted information.

The Draft Code of Practice for the Investigation of Protected Electronic Information - Part III of the Regulation of Investigatory Powers Act 2000 is open to review and comment until August 31, 2006.

It is interesting how a similar proposal would fare under U.S. law. The Fifth Amendment of the U.S. Constitution may in fact prevent seizing encryption keys if the ‘actions which would render testimony against oneself’ are considered covered under the protections of the Fifth Amendment. It can be argued that there is no difference between the demand for someone to surrender their encryption key and their ‘giving testimony or surrendering evidence against themselves.’  Many would point to the example of the safe combination and whether law enforcement can force someone to divulge the combination to the safe where incriminating evidence would be found. Although the Framers did not specifically envision complicated encryption keys being used to protect incriminating evidence, they certainly sought to protect one from having to serve on a silver platter information to law enforcement which would then be used to obtain conviction.