Mr Li Shengwu, 32, a nephew of Prime Minister Lee Hsien Loong, has been taken to court for a Facebook post saying that "the Singapore Government is very litigious and has a pliant court system".
The Attorney-General's Chambers (AGC) initiated the move, and the first pre-trial conference was held at the High Court yesterday.
The Straits Times understands that Mr Li - the eldest son of Mr Lee Hsien Yang, who is the younger brother of the Prime Minister - was served court papers earlier in the United States, where he is a junior fellow at Harvard University.
He is not being charged with a crime. Instead, the AGC has taken up an originating summons, typically used in civil cases.
But because the court can impose a jail sentence in contempt of court cases, these are sometimes considered "quasi-criminal" cases.
The July 15 post was related to the dispute between Mr Li's father and aunt Lee Wei Ling on one side, and his uncle on the other, over their late father's Oxley Road home.
The AGC had written to Mr Li asking him to apologise but he declined, saying his post was private. He subsequently amended parts of it. Mr Li also contended that the post, when read in context, did not constitute contempt of court.
The AGC called the post an "egregious and baseless attack" on the judiciary. It applied for and was granted the court's permission to initiate contempt of court proceedings in August.
At yesterday's conference, Assistant Registrar James Elisha Lee set the next pre-trial conference for Dec 4, to give Mr Li's counsel, Mr Abraham Vergis, time to review the court papers that have been filed so far. Mr Vergis, of Providence Law, said the AGC had not told the court what it was asking for - a fine or a jail term.
The AGC was represented by Senior Counsel Francis Ng, who declined to comment.
Two prominent contempt of court cases in recent memory have ended in fines. Lawyer Eugene Thuraisingam was fined $6,000 in August, and blogger Alex Au was fined $8,000 in 2015 - both for comments that undermined confidence in the judiciary.
Asked by reporters if Mr Li intended to return to Singapore if a jail sentence was imposed, Mr Vergis said that as the case was still in its early stages, it was premature to be discussing that.
Mr Li left Singapore for the United States on July 23.
He later told the Reuters news agency that he left more than a week sooner than planned because he thought he might be detained by the authorities over the issue.