Extremely specious white lies not unusual when one's questioned? (7,7)

I believe the answer is:

hostile witness

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'one's questioned?' is the definition.
I can't judge whether this defines the answer.

'extremely specious white lies not unusual' is the wordplay.
'extremely' suggests removing the centre (only the extremes of the word are used).
'unusual' indicates anagramming the letters.
'specious' with its middle taken out is 'ss'.
'ss'+'white'+'lies'+'not'='sswhiteliesnot'
'sswhiteliesnot' with letters rearranged gives 'HOSTILE WITNESS'.

'when' is the link.

Can you help me to learn more?

(Another definition for hostile witness that I've seen is " One testifying unexpectedly".)

I've seen this clue in The Times.

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