Catches prisoners stealing land (9)

I believe the answer is:

contracts

'catches' is the definition.
(to catch an illness is to contract it)

'prisoners stealing land' is the wordplay.
'prisoners' becomes 'cons' (short for convicts).
'stealing' is an insertion indicator.
'land' becomes 'tract' (I've seen this in other clues).
'cons' enclosing 'tract' is 'CONTRACTS'.

(Another definition for contracts that I've seen is " Legal agreements".)

I've seen this clue in The Guardian.

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