Attorneys rue complexity of Government bond (8,4)

I believe the answer is:

treasury note

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

'government bond' is the definition.
(I know that Treasury note is a type of Treasury)

'attorneys rue complexity' is the wordplay.
'attorneys rue' can be anagrammed to 'TREASURY NOTE'.
Though, I'm not sure how this is indicated.

'of' acts as a link.

Can you help me to learn more?

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

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