The founder of Scenic Hotel group and his wife are seeking a maximum of $2.3m between them in damages from Labour leader Andrew Little after suing him for defamation.
Earl Hagaman and his wife Lani have brought the action after Mr Little questioned the nature of a $100,000 donation the couple made to the National Party in 2014.
They're both seeking a maximum of $2.3 million between them.
A jury of nine men and three women was selected at the Wellington High Court on Monday morning to hear the civil trial which is set down for five days.
Mr Little is set to appear in person as a witness on Thursday.
A month after the six-figure donation, the Hagaman's company won a tender to manage the Matavai resort in Niue, which receives funding from the New Zealand government via international development assistance funds.
Months later the hotel's owners were awarded a $7.5 million grant to upgrade the resort.
Last April, Mr Little criticised the deal.
The Hagamans gave Mr Little a deadline to apologise, but the Labour leader failed to meet that deadline.
Mr Little did eventually apologise and offer to pay $100,000 towards the Hagamans legal costs but only after the hotel deal was cleared by Auditor-General Lyn Provost.
The Hagamans refused to stop court action, saying they'd spent $200,000 in legal fees preparing the case and struggled to believe Mr Little's apology was genuine.
In his opening statements, the Hagamans lawyer Richard Fowler QC said a media statement released last April by Mr Little and subsequent media statements falsely accused the couple of corruption.
The statement from April 18, 2016 read: "This looks like the latest in a line of questionable deals from John Key's Government which has seen New Zealand slide down international corruption rankings, says Little".
Mr Fowler noted Mr Little took time to write out the press release and take it to media himself.
The Hagamans are seeking $550,000 each in damages for the initial written statement, as well as $120,000 each for the five subsequent statements Little made in the media.
In total, the couple are seeking maximum damages of $2.3 million between them.
Mr Little does not deny making the statements, instead he is arguing he had qualified privilege when making them.
Scenic Hotels Limited employs around 1000 staff and runs 18 hotels, 16 of which are in New Zealand.
Mr Hagaman, 91, is housebound due to poor health, but his business partner and wife of 25 years Lani Hagaman told the court on Monday her husband was "furious" and "upset" about Mr Little's statements.
Mr Fowler said the Hagamans were "very wealthy by New Zealand standards", but asked the jury, "why should they be out of pocker, even if they are wealthy, for Mr Little's wrongdoing?"
Mr Little twice apologised and offered to pay $100,000 towards legal costs, but both offers were rejected by the Hagamans.
His most recent apology on March 24 this year was described by Lani Hagaman as "very late" and "not adequate".
Mr Fowler told the court the saga could have been resolved "a long time ago" if Mr Little just "faced the truth" and apologised.
Mr Fowler described the Labour leader's apologies as "too little, too late."
The trial continues.