Crossword Genius

How some pub employees are imprisoned? (3,6,4)

Ross

I believe the answer is:

put behind bars

I'm a little stuck... Click here to teach me more about this clue!

'how some' is the definition.
I can't tell whether this definition defines the answer.

'pub employees are imprisoned?' is the wordplay.
I cannot quite understand how this works, but
'pub' could be 'bar' (both are drinking establishments) and 'bar' is located in the answer.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.
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