IPA s.56 (Exclusion of matters from legal proceedings etc.

[Roland Perry]

In article 
<CACAki+vU+1Q9DPpyf2LyLuYmDjrf53yu3mNSQ1HF7TK2NOaCtA at mail.gmail.com>, 
Mark Lomas <ukcrypto at absent-minded.com> writes
>I agree with Roland's interpretation. Section 56(1)(a) requires that
>you should not disclose content or secondary data unless it is
>available from another source. It does not permit you to lie about that
>source.
>
>However, it would also appear to preclude a defendant from suggesting
>that intercept evidence contradicts the evidence disclosed by the
>prosecution.
>
>Usually the prosecution is obliged to disclose all available evidence
>to the defence, which provides a safeguard against bias in selection or
>presentation. Intercept evidence is exempted from that rule. Rather
>than ask about lies - deliberate dishonesty - it might be better to ask
>what safeguards are (or should be) in place to recognise when intercept
>evidence might support a defendant's case.

The difficulty with that is explaining to the court how the intercept 
evidence was obtained, and why it's relevant to the defendant, also 
breaches the 'tradecraft' rule.

This specific policy issue has been batted backwards and forwards for a 
very long time (pre-RIPA even).

I remember when, at the time of RIPA, and a few years after, the 
existence of the cellsite location information which we take for granted 
today, was also a 'tradecraft secret' and voluntarily wasn't used in 
court.

iirc the police eventually broke that embargo when they had a difficult 
kidnapping case which required the confluence of the victim and gang's 
cellsite information to prove they did it.
-- 
Roland Perry