Legal compulsion and self-incriminating passphrase

[Nicholas Bohm]

On Thu, 9 Jul 1998, Caspar Bowden wrote:

> Now I'm really confused. Nicholas Bohm thinks it might hold water, David
> Swarbrick thinks it doesn't depending on whether previous use of the
> passphrase is something that can be searched for (although no trace of it
> remains), and Michael Froomkin says no passphrase can be testimonial

Sorry.  What I should have said was that I didn't know enough about the
rule against self-incrimination to say positively that the "incriminating
passphrase" trick would not work, but that if it did it would be legislated
against fairly promptly.

Having now read a number of self-incrimination cases, I find the privilege
quite frequently overriden by statute, or held to be inapplicable where
immunity is given against use of the incriminating statement in criminal
proceedings.  There is no concept in the UK, as far as I can see, of
"non-testimonial" statements; but since a passphrase is on the current
hypothesis chosen deliberately by the self incriminator as a way of
excluding his obligation, it seems a good set of facts on which a court
might invent the concept.  So I have now become very doubtful that the
trick would work.

The European Convention, Article 6, gives the right to a fair trial.  In
the Saunders case (summarised report below this message) this was held to
cover the use of compulsory but self-incriminating statements.  The
incorporation of the Convention into UK domestic law may increase the
frequency of argument on this basis, but I doubt whether it will lead to
rapid or wholesale change in the current balance.  

It remains the case that we are talking about new legislation giving new
powers to insist on the decryption of encrypted material, and it will be
important to scrutinise it carefully to see how it works, what obligations
it imposes on whom, what excuses are available, and what responses are
satisfactory (in particular, plaintext or session key rather than decrypted
decryption key).

	Regards,

		Nicholas Bohm

Salkyns, Great Canfield,
Takeley, Bishop's Stortford CM22 6SX, UK

Phone		01279 870285	(+44 1279 870285)
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PGP RSA 1024 bit public key ID: 0x08340015.  Fingerprint:
9E 15 FB 2A 54 96 24 37  98 A2 E0 D1 34 13 48 07
PGP DSS/DH 1024/3072 public key ID: 0x899DD7FF.  Fingerprint:
5248 1320 B42E 84FC 1E8B  A9E6 0912 AE66 899D D7FF

Saunders v United Kingdom

S was interviewed by DTI inspectors as part of a statutory inquiry into
allegations that, while S was chief executive officer of Guinness Plc, the
company had taken part in an illegal share support operation to gain
advantage in a takeover battle. S was obliged to answer the questions put
to him by the inspectors or face contempt of court proceedings. Transcripts
of the interviews were passed to the CPS and subsequently to the police
who, following an investigation, charged S with theft, false accounting and
conspiracy. During S's trial, evidence obtained by the inspectors was
admitted and transcripts of the interviews were read to the jury, despite
objections by S. S was convicted on 12 counts and was initially sentenced
to five years' imprisonment, subsequently reduced to two and a half years
on appeal. Following numerous appeals in the UK courts, S applied to the
European Commission of Human Rights, alleging violation of his right to a
fair hearing under the European Convention on Human Rights 1950 Art.6.1
because the disclosure in criminal proceedings of statements obtained under
legal compulsion in non-judicial proceedings infringed his right not to
incriminate himself.

Held, (by 16 votes to four), that the right not to incriminate oneself by
remaining silent during interviews was an internationally recognised
standard central to the concept of a fair hearing under Art.6. Whether S's
right had been infringed depended on the use made by the prosecution during
the trial of statements S had been obliged to make. It was irrelevant that
the statements were not in themselves incriminating, in the sense of making
admissions of guilt, as even neutral evidence could be used in a manner
that aided the prosecution. Here the prosecution had used the statements in
an incriminating way to prove S's involvement in the unlawful operations
and to suggest that S was dishonest. The reading out of the statements
during the trial could not be justified by the need to combat fraud and,
accordingly, there had been a violation of Art.6.1. The court declined to
award compensation, but did award costs.

Court:	(ECHR) European Court of Human Rights
Judge:	R Bernhardt (President)
Judgment date:	December 17, 1996
Reported:	[1998] 1 B.C.L.C. 362; (1997) 23 E.H.R.R. 313; (1997) 2 B.H.R.C.
358; [1997] B.C.C. 872
Reference:	Times, December 18, 1996; Independent, January 14, 1997