It is like the requirement in some jurisdictions that when asked by a policeman, you must give your correct name.

If he's a kid trying to with-hold some lame porn, he may be just plain stupid.

If he's a budding anarchist/terrorist with stuff on the machine which will incriminate his fellow a/ts, then he's well trained.

If he's a child pornographer/paedophile who's fighting hard to stay out of jail and keep his suppliers uncompromised, he deserves to be there.

This is not a 5th amendment issue because the UK has no 5th.

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