Wahroonga lawyer Dev Menon, 33, was one of 10 people arrested last week over an allegedly fraudulent scheme that skimmed $165 million in taxes through a complex web of payroll businesses.

The syndicate allegedly included the son and daughter of Australian Taxation Office deputy commissioner Michael Cranston, who has also been charged with related offences.

Mr Menon, from Clamenz Lawyers, is captured in hundreds of phone taps, allegedly advising the members on how to structure and disguise a series of sub-contractor companies run by 'straw' directors.

He also held regular meetings at Clamenz's office on the 46th floor of Sydney's MLC Building, including one on February 1 in which alleged syndicate member Daniel Rostankovski and journalist Steve Barrett, according to police, extorted $5 million from the group. Mr Barrett is not facing charges.

Mr Menon is accused of spending some of the proceeds on at least three properties, including a $752,000 penthouse in Ultimo and a $2.3 million Wahroonga mansion he shares with his fiancee.

Court documents reveal that the Law Society of NSW has been trying for years to get Mr Menon, Clamenz partner Daniel Clarke and another colleague, Peter Webb, struck off for misconduct.

Complaints were made in 2012 that the trio were misusing their position as solicitors to obtain motor vehicle registration details for debt collectors.

On 10 occasions, the Roads and Traffic Authority handed over rego details on the strict condition that they were to be used in legal proceedings related to car accidents.

However, none of the cars had been involved in accidents. The trio instead passed the details on to a debt recovery company Identisearch, the Law Society claimed.

Mr Webb appeared to have started the practice and his colleagues continued it out of "poor management, poor judgment, lack of ethics and a misguided sense of duty to an existing client", the Law Society's investigator concluded.

The Law Society pursued them for professional misconduct. However, in September, Mr Menon and Mr Clarke successfully had the case thrown out by arguing that the society's reasons were not of the standard required by law.

They said the investigation was irrational and illogical and "so unreasonable that no reasonable decision maker could have made it".

It's understood the society will pursue the matter again in the coming months.

Mr Menon was granted bail last week on charges of conspiracy to defraud the Commonwealth after his father offered a $100,000 surety.

As the ATO appeared to close in on the syndicate in January, Mr Menon was allegedly recorded in a phone call with Mr Rostankovski saying: "F--- this is defcon 5 man."

He said sub-contracted companies should set up new bank accounts to pay unpaid tax bills that had triggered garnishee orders from the ATO, according to police documents tendered in court.

"I think it's the bank, I don't think it's the government, I don't think it's the ATO or anything ... [but] what's scary is between you and me, I'm telling you this, man, if we don't pay this today I know [alleged co-conspirator] Simon [Anquetil] is going to pull the plug, like that's it, all over."

Mr Clarke has not been charged over the alleged tax fraud but was named as one of 15 people that the co-conspirators are not allowed to contact while on bail.

Clamenz Lawyers is listed online as being a subsidiary of Synep, the company allegedly set up by Adam Cranston to buy out Plutus Payroll and set up the scheme.

A spokeswoman for the Law Society would not comment on Mr Menon but said a solicitor must notify the Law Society within seven days if he or she is charged with a tax offence.

"If a solicitor is convicted for a serious offence or a tax offence they must, within 28 days, provide a written statement setting out the facts and circumstances of the event and explain why, despite the show cause event, they consider themselves to be a fit and proper person to hold a certificate," she said.

Clamenz Lawyers was contacted for comment.