Independent MP Brendan Horan is being sued by convicted tax avoider and former friend Colin Henderson for defamation.
Henderson has filed a case in the Auckland High Court seeking $350,000 from Horan and damages from media company Mediaworks over comments made by Horan on Radio Live.
Lawyer Brian Henry, who has also represented New Zealand First leader Winston Peters, confirmed he had filed the suit on Henderson's behalf over the comments.
He confirmed Henderson was seeking $350,000 from Horan but could not confirm the amount sought from Mediaworks.
Horan told Fairfax he was yet to be served papers and only become aware of the action after being contacted by media. He dismissed the case as politcally motivated, saying he had more important things to do.
Peters, in turn, dismissed Horan's claim as "bulldust", saying he had no involvement and had not referred Henderson to Henry.
Henderson, a former clothing importer, and his failed company, House of Pagani (NZ), were fined $800,000 plus legal costs of $41,400 on 120 charges involving smuggled clothing from Asia in 1997.
Henderson used to board with Horan and his wife before the pair fell out.
It is the latest in a series of allegations levelled at Horan after he was dumped as an MP by NZ First over claims surrounding the financial affairs of his late mother.
An enquiry by the executor of Olwen Horan's will found there was no evidence of misspending by Horan, who denies the allegations, though a separate police investigation is underway.
A spokeswoman for Mediaworks declined to comment as the matter was before the courts.
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