Unprecedented tax investigations have been launched on hundreds of gangsters and their white-collar associates in an attempt to claw back unpaid revenue and disrupt their day to day activities.

HM Revenue and Customs (HMRC) is scrutinising the lifestyles of Scotland's 600 most dangerous organised criminals, including lawyers, accountants and other associates.

In a joint operation with police reminiscent of the 1931 tax evasion trial of Chicago mobster Al Capone, police have turned over crucial intelligence on gangsters to the taxman.

The HMRC for the last 18 months has been methodically going through the tax affairs of the top 20 per cent of the more than 3000 men and women detailed in Scotland's constantly updated crime "map", the police's core intelligence tool on the underworld.

The aim is not only to secure unpaid tax but to disrupt the day-to-day activities of organised criminals, their enablers and front organisations.

The Herald:

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David Odd, assistant director, Fraud Investigation Service, HMRC, said forensic accountants were pouring over the finances of flagged "prominent nominals", the most troublesome criminals on the map, looking at anything from holiday homes to cars that show them living beyond their means.

Mr Odd said: "Both the police and HMRC have a legion of professional highly trained financial investigators who use the tools available to them in the law to build up a financial picture of suspects.

"It is everything. When they construct a financial profile they want to account for every penny in somebody’s life, spent and received.

"We are talking about everything, absolutely everything."

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Investigations are focused on income tax, corporation tax, inheritance tax and charitable activities, as well as the more traditional HMRC work on criminal evasion of excise on tobacco and alcohol.

HMRC and Police Scotland, which both have a heavy emphasis on targeting organised crime, share a base at the still new Scottish Crime Campus, in Gartcosh, North Lanarkshire.

This proximity, closer than ever, means they and the Crown Office are able to share intelligence like never before.

Increasingly that means that Mr Odd's colleagues are able to use civil, as well as criminal, measures against underworld figures flagged up on the crime map and detailed in the Scottish Intelligence Database.

The Herald:

Mr Odd, pictured above, added: "There are up to 3500 or so people identified in the crime map. The top 20 per cent are under continued intervention.

"We are committed to deliver HMRC civil investigations in relation to all of those cases."

Mr Odd stressed that his team's investigations would not always lead to civil actions or that only the top 20 per cent would ever be targetted.

But police and other law enforcement agencies are increasingly aware that just scrutiny - even without formal action - can have a crippling effect on organised crime.

As with civil and other proceeds of crime recoveries their key measure is whether they stopped or reduced activity by criminals, not whether they bagged a lot of money.

So HMRC has had to undergo a cultural change in order to chase criminals rather than money. They body's key aim has always been to "narrow the tax gap", raise revenue.

The Herald:

But now it is changing its rules of engagement, where how much cash it can raise is not its only measure of success.

Mr Odd said: "There is a compromise for us. We will contemplate interventions that would not normally take place under our own risk rules."

HMRC and Police Scotland have made it clear that they are not just tackling the street gangsters who feature in crime reports.

They are after the apparently legitimate entrepreneurs and professionals who wield much of the real power in the underworld.

Mr Odd said: "Your status in society is not a protection. That just does not enter in what we think about. The professionals are right on our radar."

The Herald:

Crucially, such white-collar criminals often avoid action in the criminal courts but would struggle to explain their spending patterns. Police have been targetting such specialists for some years, as first revealed by The Herald.

Mr Odd confirmed that civil tax matters were being explored even while parallel criminal investigations are underway.

Evidence from the two processes must be kept apart, firewalls put in place to ensure a civil process does not contaminate a criminal one.

Mr Odd is unaware of such tactics ever being adopted before. They were, he said, "vanishingly rare".

Detective Chief Superintendent Gerry McLean, who leads on organised crime for Police Scotland, stressed Gartcosh had created such innovations as partners in the campus looked at new "tactical options" at joint meetings.

He said: "Rather than exhausting conventional law enforcement tactics we are able to set up an investigation to be more efficient and impactive by looking across the entire table."

The Herald:

How this story looked in print.