Tops two thousand in legal actions (7)

I believe the answer is:

summits

'tops' is the definition.
(I know this)

'two thousand in legal actions' is the wordplay.
'two thousand' becomes 'mm'.
'in' means one lot of letters goes inside another.
'legal actions' becomes 'suits' ('suit' can be a synonym of 'legal action').
'mm' put within 'suits' is 'SUMMITS'.

(Another definition for summits that I've seen is " tops".)

I've seen this clue in The Globe and Mail.

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