Immigration Minister Scott Morrison has moved to urgently review the man's visa, which should have expired in 2010, after Fairfax Media alerted his office to the bungle.

The case is especially sensitive for the Liberal Party because of its links to a Mafia political donations scandal that includes funds raised at the 2013 election. Documents obtained by Fairfax Media reveal the man's visa should have expired or been cancelled in 2010.

A spokesman for Mr Morrison said the Mafia figure's visa case ''was not brought forward'' by the Immigration Department for his consideration, or of his Labor predecessors, ''until now''.

The Mafia figure's five-year visa was granted to him by the Howard government in 2005 after the man's associates raised tens of thousands of dollars for the Liberal Party in a donations-for-visa scandal later investigated by the federal police.

Prior to his visa being issued, authorities had urged the government to deport the convicted Mafioso because he was a violent and dangerous criminal.

His five-year visa included provisions that required the repayment of almost $250,000 to the Commonwealth and maintaining a good character.

But the man, who has not repaid his debt, was arrested for drug trafficking and murder charges in 2008 and 2009 and, earlier this year, was investigated over the shooting up of several Melbourne pizza restaurants.

The revelations come after Fairfax Media on Friday revealed one of the man's closest associates, a suspected crime boss who led the donations and lobbying campaign to help get the Mafioso a visa, had donated again to the Liberals last year - despite some in the party knowing of his alleged ties to organised crime.

The donor, who police suspect is the alleged Calabrian Mafia godfather of Melbourne, helped bankroll the Liberal Party's campaign to win the marginal federal seat of Bruce at the 2013 election. Neither the alleged Mafia boss nor his associate who was granted a visa can be named due to a court suppression order.

On March 1, 2013, the alleged Mafia boss helped host the $250-a-head ''Bruce Campaign Fundraising Dinner'' at his Docklands reception centre, which he co-owns with the criminal figure who was granted a visa.

The event was attended by several state and federal Liberal MPs including Russell Broadbent and guest speaker, state Planning Minister Matthew Guy.

The alleged crime figure's fund-raising occurred despite Mr Broadbent and other Liberal attendees knowing of the alleged Mafia boss's suspected involvement in organised crime.

Asked about the fund-raising scandal on Friday, Premier Denis Napthine refused to comment, claiming it was up to the Liberal Party to provide an explanation for the event. ''It is not a matter for me,'' Dr Napthine said. ''I don't even know who they are talking about.''

Labor is leaving open the possibility of referring the allegations to the commission. Deputy Opposition Leader James Merlino said it was ''unbelievable'' that Mr Guy had appeared as a headline speaker without checking who had organised the event.

Greens upper house MP Sue Pennicuik said the revelations provided an ''extreme example'' of the lack of transparency and accountability in political fund-raising. She said the Greens were preparing legislation that would ban political parties from accepting donations from property developers.

Mr Broadbent was previously embroiled in the donations-for-visa scandal after he lobbied the government for the crime figure to be granted a visa on humanitarian grounds. He has refused to comment. The suspected Mafia boss is a long-time supporter of the Liberals in Victoria's south-east, where he is seen as being able to influence votes of some residents of Calabrian heritage.

The alleged Mafia boss has been previously described by police in court as a person allegedly involved in ''murder, gunshot wounding and arson''.

He was named as a suspected hitman in two coronial inquests in the 1990s and identified in a recent police intelligence briefing as the leader of a ''well established'' Calabrian Mafia cell in Melbourne that remains a powerful presence at Victoria's wholesale fruit and vegetable market.

A spokesperson for the Minister for Immigration and Border Protection denied any error on the part of the department.

“The Minister is advised that the individual was granted a permanent visa in 2005 when the then minister used her personal and non-compellable power to intervene in the case. The Minister is advised by the Department that the then Minister had the facts before her – including both the individual’s criminal record and the mitigating factors upon which he was seeking to remain in Australia," the spokesperson said.

“This is standard practice for all ministerial intervention requests, where the arguments for and against are put to the minister to inform the minister’s consideration.

“Following that grant of a visa, it is a matter of public record that this person has been charged with other serious criminal offences.

“The department is well aware of this case, however, it is awaiting the outcome of that court process and if the individual is found guilty, at that stage the department makes an assessment of whether the individual fails the character test and considers whether cancellation is appropriate under Section 501 of the Migration Act.

“Natural justice and the concept of innocent until proven guilty must apply in any departmental assessment."

“However, it does remain open to the minister (but not the department) to consider cancellation using personal powers under s.501, without natural justice processes, if he deems it in the national interest to do so. If the minister is inclined to consider such a course of action, the department ensures he has all relevant material to allow him to make an informed decision.”

Despite being the subject of numerous organised crime probes, the alleged mob boss has never been charged with a criminal offence and denies any involvement in organised crime or political bribery. The federal police bribery probe was closed in late 2009 after gathering insufficient evidence.