The man who triggered a gambling regulator’s “most significant decision of the decade” has urged federal politicians to launch a “radical intervention” to stop the harm caused by online sports gambling.

The former financial adviser Gavin Fineff stole millions of dollars from his clients and friends – some of whom were elderly and vulnerable – to service his gambling addiction. He lost more than $8m to sports betting companies, which has not been returned to his victims.

Last month, the Northern Territory Racing Commission (NTRC), which regulates almost all online betting companies in Australia, found Ladbrokes did not investigate the source of Fineff’s money and whether he could afford deposits of $2.2m over a 21-month period. Ladbrokes instead offered bonus incentives worth $528,890 to entice him to spend more.

Fineff is in custody awaiting sentencing after pleading guilty to multiple fraud charges. In a statement read by his mother, Lyn, he told a meeting of the parliamentary friends of gambling harm reduction in Canberra on Wednesday that “radical intervention” was needed.

“The industry has taken advantage of the profit taking opportunity and appreciated the ‘poor eyesight’ of regulators,” Fineff said in the statement.

“I should have been stopped and it would have been so easy. Why wasn’t I stopped? Why was I given millions of dollars of free bets? Why were the red flags and monitoring alerts ignored?”

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Ladbrokes was fined nearly $80,000 for serious breaches of its licence while dealing with Fineff. The regulator found Ladbrokes “appeared to have been more focused on realising its own profits from the gambler rather than ensuring that it was providing a responsible gambling environment”.

“At the very minimum [Ladbrokes] should have undertaken some form of thorough and rigorous inquiry as to the gambler’s source of wealth,” the NTRC said.

Lyn told politicians her son had taken responsibility for his crimes and was now trying to make amends for the damage he caused.

“What needs to happen so the next me is stopped? Because I promise you, he or she, in their minds, is fixing a problem, not making one far worse,” Fineff said in the statement.

Fineff worked with the independent MP Andrew Wilkie to draft legislation that places a positive onus on gambling companies to report suspicious transactions and proceeds of crime to authorities.

“The brutal reality is that many tens of thousands of Australians are addicted to gambling, in particular poker machines and online betting, and it’s a terrible reflection on federal, state and territory governments that this is allowed to continue unchecked,” Wilkie said.

Fineff said an ongoing inquiry into harm caused by online gambling was “a unique opportunity” for the federal government to listen to community sentiment and plan intervention.

“Now is the time to strive mightily and effect real change,” Fineff told the politicians.

When Labrokes was fined, its parent company Entain, accepted the criticism of “interactions between a former customer and a former VIP manager between 2017 and 2019”.

“Entain Australia accepts the NTRC ruling, and since these interactions occurred it has invested significantly to strengthen its approach to customer protection,” an Entain spokesperson said.

Australia has the highest gambling losses of any country, at an average of $1,276 a person each year, with problem gambling rates more than doubling from 0.6% of the adult population in 2011 to 1.23% in 2019.

• In Australia, Gambling Help Online is available on 1800 858 858. The National Debt Helpline is at 1800 007 007. In the UK, support for problem gambling can be found through GamCare on 0808 8020 133. In the US, the National Council on Problem Gambling is on 800-522-4700