The Nationalist Party has accused Labour deputy leader Anġlu Farrugia of being unfit to occupy his post after he questioned a court judgment last week.
Speaking in Parliament, Dr Farrugia urged the Attorney General to appeal against a court decision which acquitted a businessman accused of corrupt practices. He also asked whether the court had correctly interpreted the law.
Pierre Bartolo was cleared of charges that he had tried to force employees to vote for the PN in the 2008 general election after Dr Farrugia filed a police report claiming a number of votes were rigged.
The PL deputy leader's statement prompted a strongly-worded statement from the PN, which described Dr Farrugia's actions as "dangerous and seriously lacking in respect towards democracy, human dignity and the judiciary's autonomy".
It said his actions were deplorable and did not befit someone occupying the post of deputy leader as well as dangerous when the same person expects to one day be deputy prime minister.
"Instead of bowing to the court's judgment and apologising for shedding a bad light on innocent people and instead of apologising to the public for trying to tarnish... a general election, (Dr Farrugia) attacked the courts because the verdict contradicts his allegations," the PN said.
The PN also criticised PL leader Joseph Muscat for being "incapable" of condemning his deputy, questioning whether Dr Farrugia would continue occupying his post as though nothing had happened.
The PN called on Dr Muscat and his party to dissociate themselves from Dr Farrugia and apologise to the public and the judiciary.
When contacted, Dr Farrugia said he had exercised the democratic right to react in Parliament to a court decision.
"Irrespective of the PN spin, the fact is that the court found that a person was threatened to vote for the PN... If by Lawrence Gonzi's PN standards it is okay to threaten someone with losing her job if she does not vote in a particular manner (irrespective for which party), for me it is not."
Dr Farrugia said he relayed to police any information that came to his knowledge like any citizen should do.
He said this was a far cry from the inaction by government ministers and officials when faced with allegations.
"The PN has long embarked on a predictable character assassination campaign in my regard. It is ironic how the PN is trying to throw malicious innuendos when they know the facts."
He said that back in 1987, when the PN was elected to power, he was appointed to investigate and prosecute members of the police force in the Nardu Debono murder trial.
"I do not think I could have been entrusted with such a task by the Nationalist administration of the time, unless I was trusted in my work.
"I carried out this difficult task, investigated, prosecuted and served my country without fear or favour. I have since continued to do so in politics. I will keep vying to clean politics from corruption."