Blogger Han Hui Hui has removed a series of online posts and a video in which she alleged judges had lied to persecute her politically, after the Attorney-General's Chambers (AGC) warned her that her claims were in contempt of court.
She has also apologised on her social media accounts and stated that she will not repeat the allegations, the AGC said in a statement yesterday.
Had she not done so, it would have commenced contempt of court proceedings against her.
The AGC said parts of her video and posts "scandalised the Singapore courts by stating that the Singapore courts had lied, that they were politically motivated in convicting and sentencing her, and that they sought to persecute and harass her".
"Her statements were scurrilous, false and made without any rational basis," it said.
Ms Han, 25, had posted a video on YouTube and made five Facebook postings between Jan 21 and Feb 25 about her brush with the law.
Last June, she was fined $3,100 for co-organising a protest rally in 2014 that disrupted a charity event in Hong Lim Park and organising a demonstration without approval. Last month, the High Court rejected her appeal against the ruling.
The AGC wrote to her on March 13, informing her that the video and posts were in contempt of court. For instance, a Jan 22 post "wrongfully states that you and the other co-accused persons tried jointly with you were convicted because the court wanted to politically persecute you and your co-accused".
The AGC added: "It wrongfully insinuates the court secured your convictions by deliberately finding fault with you on unimportant issues."
Ms Han had written in the Jan 22 post that the court's ruling was "a blatant case of political persecution". She also said her fine had "the sole intention of political persecution to disqualify me from standing for parliamentary election".
A person convicted of an offence and fined $2,000 or more is disqualified from being an election candidate. Ms Han stood in Radin Mas in the 2015 General Election.
The AGC gave her seven days to take down the posts and apologise for her allegations on all her social media accounts.
Yesterday, the AGC reiterated that contempt of court in its various forms harms the proper administration of justice in Singapore.
"Left unchecked, such conduct can obstruct the determination of the truth and erode respect for our judicial institutions. This would in turn harm the public interest in the proper administration of justice.
"AGC will take firm action against contempt of court, including the institution of committal proceedings in appropriate instances," it added.