Updated 4pm, adds Jason Azzopardi's comments
Magistrate Nadine Lia was warned in an anonymous letter that her career and marriage would be destroyed if she did not remove herself from a case concerning the defunct Pilatus bank.
The Association of Judges and Magistrates of Malta revealed the contents of the letter in a statement in which it also condemned the threat.
Lia received the letter at home, threatening her, her family and her work, the association said.
"We told you to remove yourself. Now enjoy watching us destroy your career and marriage. Are you happy? Next time obey just like the others do. Omerta Si. Sfidare No," the letter read.
The magistrate is hearing a case filed by civil society group Repubblika against the police commissioner and attorney general, who the NGO says have failed to press charges against various Pilatus officials, despite the recommendations of an inquiry.
Repubblika has also condemned the threat.
The judiciary association said such acts of intimidation should be condemned and can never be accepted in a democratic society where the principle of rule of law is observed.
"Members of the judiciary should be allowed to carry out duties in a serene way and without any form of pressure or fear for their own safety or that of their family," the association said.
It said that the judiciary understands and accepts criticism but people should never turn to pressure, intimidation or threats.
The association said it expresses solidarity with those members of the judiciary who are threatened and called on the authorities to ensure the judiciary's safety.
Earlier on Thursday, Magistrate Lia confirmed in court she had received the anonymous letter two days before.
She has refused to recuse herself from the case.
Repubblika has argued that Lia is unfit to hear the case, because of her ties to lawyer Pawlu Lia, who is her father-in-law.
Pawlu Lia also serves as a lawyer to former prime minister Joseph Muscat, and Repubblika says that link means the magistrate has a conflict of interest, given the history involving Pilatus and Muscat.
The magisterial inquiry recommended police criminally charge six Pilatus Bank officials.
Apart from Pilatus Bank itself, only one of the six Pilatus Bank officials mentioned in the conclusions – Claude-Ann Sant Fournier – has been charged in court.
The other five - Luis Felipe Rivera, Mehmet Tasli, Sayad Ali Sadr Hasheminejad, Antonella Jane Gauci and Hamidreza Ghambari – have not.
In a post on Facebook, lawyer and former MP Jason Azzopardi, a lawyer, referred to the statement issued by the judiciary association and wondered why the association had not commented in the past when a member of the judiciary had been intimidated by a prime minister, a former prime minister, an MP and the government’s whip, for doing her duty and authorising a search of former Prime Minister Joseph Muscat’s home.