Upcoming police department has one rule that might be basic (9)

I believe the answer is:

nonacidic

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

'rule that might be basic' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'upcoming police department has one' is the wordplay.
I cannot quite understand how this works, but
'police' could be 'cid' (abbreviation for Criminal Investigation Department) and 'cid' is located in the answer.
'one' could be 'o' (I've seen this in other clues) and 'o' is located in the answer.
This explanation may well be incorrect...

Can you help me to learn more?

I've seen this clue in The Independent.

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