Pheu Thai Party prime ministerial candidate Srettha Thavisin is suing whistleblower Chuvit Kamolvisit for 500 million baht for defamation over comments made about a land purchase by property developer Sansiri Plc.
Mr Srettha was chief executive oficer of Sansiri before deciding to run for election and subsequently for prime minister.
Winyat Chartmontree, Mr Srettha's lawyer, said at the Criminal Court on Monday that his client had him file the lawsuit because Mr Chuvit's comments at a press conference on Aug 3 could mislead the public and parliamentarians into thinking his client was not a decent and honest man and should not become prime minister.
The Pheu Thai Party recently announced it would nominate Mr Srettha to the joint parliament as its candidate for prime minister.
Mr Chuvit implied land sale tax evasion in Sansiri's purchase of 400 square wah of land on Sarasin Road in Bangkok in August 2019, when Mr Srettha was still CEO.
Mr Chuvit implied that Mr Srettha and Sansiri colluded with the landowners to evade 521 million baht in taxes on the developer's purchase of the prime block of land.
The reported purchase price was 1.57 billion baht, nearly 4 million baht per square wah (4 square metres).
He said Mr Srettha signed off on the purchase and sale agreement with the 12 people who owned the land under one title deed. The 12 owners formed an "ordinary partnership", under which each one would be liable for excise tax on the proceeds of the sale, a total of 521 million baht, according to Mr Chuvit.
To avoid such a huge tax payment, Mr Chuvit said, each of the 12 individuals went to the Department of Land to transfer small sections of the land to Sansiri, taking 12 days to complete the process. These transactions were not subject to the same tax treatment as an ordinary partnership.
According to Mr Chuvit, only 59.2 million baht in taxes were paid on the transaction.
On Monday Mr Srettha's lawyer, Mr Winyat, said the previous landowners did not have to pay tax as an ordinary partnership because they acquired individual ownership of sections of the land and then sold them individually to Sansiri. As a result, the sellers were subject to personal income tax, the lawyer said.
Meanwhile, Mr Chuvit said he had more issues he could raise concerning Mr Srettha, who as a candidate for prime minister should welcome the examination of his qualifications.
Separately, activist Rueangkrai Leekitwatana has asked a senate committee to look into the same land purchase by Sansiri.