The first large-scale crackdown by the Australian Taxation Office on an outlaw motorcycle club, the Rebels, has so far netted $1.7 million.

An unknown portion of this comes from what the Australian Crime Commission calls "the criminal activity of the Rebels' business model": amphetamine sales, extortion rackets or the like.

But in tax law, the source of income is "not necessarily an issue", ATO assistant commissioner, serious non-compliance Phil Jones told The Sunday Mail in an exclusive interview.

"Whether it's legitimate or illegitimate, we still want tax paid."

When the ATO in the past stumbled on illicit cash flows, it generally did not share the information with law enforcement.

But acting as part of the ACC-led Task Force Attero, the firewall has come down.

Mr Jones said the tax office received a list of Rebels members nationwide and generated its own targets through "our normal profiling methods".

The Rebels showed "high degrees of non-lodgement, non-payment of outstanding tax debts".

Some live large: last month, the annual income of one bikie was assessed at more than $1 million.

The vast majority of businesses were in blue-collar industries, Mr Jones said.

A minority of Rebels had sophisticated financial structures, "a combination of trusts, companies, partnerships and super funds".

Offshore cash flows and interests remained under investigation, Mr Jones said.

Of 117 bikies hit with tax assessments, 34 entered payment arrangements that might include garnished wages.
Another 35 who refused to lodge tax returns have been referred for prosecution, and 10 of these have been slapped by courts with $90,000 in fines since March.