Newly promoted Victorian government minister Luba Grigorovitch has apologised for writing 33 character references – including for a taxi driver convicted of assaulting female passengers, two men accused of family violence and a supporter of former Iranian supreme leader Ayatollah Ali Khamenei – without so much as a Google search.

Grigorovitch issued a statement on Monday night confirming that, since she became the member for Koroit in late 2022, she had provided “around 33” character references, including six “to individuals that I now know I shouldn’t have”.

“At the time I provided these references, I was not aware of their history. I will no longer provide character references and I apologise for any offence I have caused,” she said in the statement.

This included two character references for constituents who had separately fought federal government decisions to revoke their visas for failing the character test – Muhammad Isa, a former taxi driver who indecently assaulted female passengers in 2013 and a 38-year-old Pakistani citizen, given the pseudonym CYNW, convicted of family violence offending against a former partner.

According to a transcript of the administrative review tribunal’s May decision, Grigorovitch had written she had known Isa for “several years” and could “confidently attest to his character, integrity, and contribution to the Australian community”.

The decision, however, noted Isa had conceded Grigorovitch was “unaware of his past offending” when she had written the reference. The ART rejected his appeal, due to “serious past crimes, implausible current narrative, and continuing lack of insight and acceptance of responsibility”.

The ART decision in the case of CYNW only stated Grigorovitch had written a character reference.

Later on Tuesday, it was revealed that Grigorovitch had also provided two character references for a man who has appeared multiple times in court listings for domestic violence offences, two references for another man who was fined for selling illegal merchandise at local markets and an immigration reference for a man who had appeared before the Melbourne magistrates’ court at least once.

She had also written a “letter of support” for a man whom the government believes is a supporter of Khamenei.

Speaking outside parliament on Tuesday, Grigorovitch admitted neither she or her office had Googled anyone prior to providing a character reference.

“We didn’t have a process. People would ask for a character reference, I took them on on face value and I provided a character reference,” she told reporters.

“I should have done more before giving those character references.”

Grigorovitch said she knew each of the people she provided characters to because they were “volunteers within the community”.

She said she was not aware of them being union-affiliated, though they “might be Labor members”.

“My process is not good enough, and that is why I’ve come here today and I’ve apologised and said that I should not have provided a character reference,” Grigorovitch said. “Going forward, I will not be providing character references. Full stop.”

She said she realised it was a “mistake” and “it won’t happen again”.

In question time on Tuesday, the premier, Jacinta Allan, said Grigorovitch was “not aware of their backgrounds” at the time she penned the references.

“I have confidence in all of my ministers,” she said.

Grigorovitch, a former state secretary of the Rail, Tram and Bus Union, was elevated to the cabinet by Allan in April and given the portfolios of youth, carers and volunteers.

She immediately drew headlines after saying she had “no regrets” about her past friendship with former construction union leader John Setka, who she worked with closely at the RBTU. She also thanked Setka personally in her maiden speech in 2023 and he attended her wedding that same year.

The shadow attorney general, James Newbury, who in April criticised Grigorovitch’s elevation to cabinet due to her ties to Setka, said the revelations about the character references were further proof she was “not fit to be a minister”.

“If this government had any integrity, she would be sacked,” he said. “It has no integrity. So, I’m sure there should be a thriving part of that ministry up until election day.”

He said references were only acceptable in “exceptional circumstances” such as to former employees.

Government minister, Harriet Shing, said she had only ever provided a job reference.

“What I can assure people of is that it’s never been my practice to provide character references,” Shing said. “It’s something that I take really seriously.”

The Greens leader, Ellen Sandell, said she had only ever written one character reference during her 12 years as an MP, for someone she knew “personally”.

“It is a matter of common sense and good judgment that you should not be providing character references to people that you don’t know,” she said.

Earlier this year, the Liberal party was also embroiled in its own character reference scandal, with political hopeful Dinesh Gourisetty winning a preselection vote but not formally endorsed after it emerged 24 hours later that he had written a character reference for a convicted sex offender.

The party reviewed its vetting processes as a result.