lack of success.194 We took this as a sign that the SIAs were dealing frankly with
us – and also of their confidence that, viewed overall, the story they had to tell
was a positive one.
Historical and comparative usage
4.34.
I also considered, more briefly, the history of each of the powers under review,
and the extent to which it has been used by bodies other than the SIA, both in
the UK and abroad. Such use by others is of course not directly probative of
practical utility, any more than is use by the SIAs themselves. But to the extent
that others may (or may not) have troubled to develop and deploy such powers,
that fact may be an indicator of their utility and necessity.
Snowden documents
4.35.
I have also had regard to the Snowden documents. Despite the fact that for the
most part their contents have been neither confirmed nor denied [NCND] by the
Government, I have had the opportunity to question the Government privately on
various matters referred to in that material, and have received a number of
detailed briefings.
Previous reviews
4.36.
Last but not least, I thought it important to take on board the conclusions of the
other bodies which have considered the utility of the powers under review, or
similar powers – particularly those whose assessment has been informed by
detailed access to the classified detail.
4.37.
Relevant in that regard are the various reports and studies referred to in chapter
3, above. Where I have been unsure of the significance of their findings, I have
engaged where possible with those responsible in order to improve my
understanding of their conclusions.
Conclusion
4.38.
194
None of these approaches, or classes of evidence, could be determinative on its
own of the issues I am asked to consider. Some may offer no more than a
glancing or peripheral insight. But by coming at the issue from a number of
different angles, it has been possible to arrive at conclusions that I have felt able
to state with a high degree of confidence.
See e.g. 7.24-7.25 below, on EI.
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