A probe into Anthony Dieni's conduct by the Independent Broad-based Anti-corruption Com??mission has cast doubt over a series of judgments made in Victorian courts, because of allegations he gave false evidence, arranged false urine samples and took drugs as payment.

Mr Dieni???, 69, is also accused of stealing $164,000 from St Paul's Rehabilitation Prevention, the Strathmore-based charity through which he provided support to people with addiction problems.

The counsellor has previously advocated for drug trafficker Frank Madafferi, enlisted slain gangland lawyer Mario Condello as a volunteer counsellor and given favourable evidence for a senior Finks bikie. The Age is in no way suggesting that there was any impropriety on Mr Dieni's part in those cases.

Mr Dieni, of Keilor Lodge, was granted bail on Wednesday, but only after a magistrate refused to accept an Anglican archdeacon's offer of a surety because the clergyman could be called as a prosecution witness, as he founded the rehabilitation service with the accused man more than 30 years ago.

Archdeacon Philip Newman told Melbourne Magistrates Court he was prepared to provide a surety from his own personal funds so Mr Dieni could get bail.

But magistrate Ross Maxted??? was uncomfortable with the offer given Archdeacon Newman could one day give evidence against the accused.

Mr Dieni is charged with perverting the course of justice, perjury, trafficking a drug of dependence, theft and dealing in the proceeds of crime.

IBAC alleges he misled a Broadmeadows magistrate this year when advocating for Patricia Martin, one of 10 clients with cases before the courts. Martin was spared jail when a court heard she attended the St Paul's clinic and was drug-free.

IBAC investigator Emily Scott said on Wednesday thaMr Dieni arranged for a colleague at the charity, receptionist Vivien Eden, to provide a clean urine sample for Martin when the latter told him she had breached bail by taking drugs.

Ms Eden has not been charged, but the court heard IBAC's investigation was ongoing.

"It is likely there will be more people involved," Ms Scott said.

IBAC alleges Mr Dieni waived his fees for Martin and instead had her provide him with cocaine and cannabis, which he passed onto his adult grandson.

Archdeacon Newman said the charity sourced money from donations and trusts, but was unaware it had $164,000 in its account.

He said the service did not pay wages, but provided financial support for Mr Dieni and his wife.

Mr Maxted said the charity had a "lot of unanswered questions" to respond to. There was nothing to suggest the archdeacon did anything untoward, the court heard.

The charges against Mr Dieni were serious, Mr Maxted said, and touched "on the judicial administration in the state of Victoria", as magistrates and judges were reliant on counsellors to provide truthful and accurate evidence about clients.

But the magistrate granted bail after defence counsel Theo Alexander told him Mr Dieni's wife was gravely unwell and prosecutors did not oppose his release from custody.

Mr Dieni has connections to Italy, the court heard, and Mr Maxted ordered the man's son provide a $500,000 surety, after which Mr Dieni would be released.

Prosecutor Tobie Wicks said IBAC was contacting police officers who charged Mr Dieni's 10 clients, to determine whether bail arrangements should be reviewed.

Mr Dieni, who in 1997 was awarded the Medal of the Order of Australia for "service to the community", is due to return to court next week.