Reports say retired NSW Police commissioner Mick Fuller failed to declare racehorse shares to the NSW government.

Former police commissioner Mick Fuller did not declare his co-ownership of racehorses with two wealthy businessmen, according to reports this week. 

One of his fellow co-owners is embroiled in criminal investigations, while another won lucrative police contracts.

Mr Fuller submitted no conflict-of-interest declarations to the government until last year; a potential breach of anti-corruption rules.

Mr Fuller was paid over $665,000 a year as the head of Australia's largest police force from 2017. He retired last month from a 34-year career in law enforcement. 

He has been strongly tipped to be picked by NSW Cabinet to join the board of Racing NSW, the horseracing operator and regulator. Sports Minister Stuart Ayres has endorsed him as a candidate “of the highest integrity”.

Reports by the ABC say Mr Fuller was part of an exclusive group of high-ranking NSW Police Force (NSWPF) officers known as the “Punters Club” due to their love of gambling, horse racing and rugby league.

Mr Fuller and at least five others employed in leadership roles within the NSW Police Force (NSWPF) allegedly acquired shares in 2015 across at least four racehorses from high-profile trainer David Vandyke.

Mr Fuller had shares in two horses - Mad Magic and Once Epona Time - from which he would have obtained a proportion of any winnings.

But it was a poor bet, as the horses barely made any winnings.

Mr Vandyke has been fined three times since 2015 for banned substances discovered in his racehorses in NSW and Queensland. 

The NSWPF code of conduct required Mr Fuller to declare to the government any private interests, social activities or relationships that could, or could be perceived to, influence his decisions.

Mr Fuller filed a private interest declaration to the NSW Department of Premier and Cabinet last year, after he had given up his shares.

Experts have called for an independent investigation into the allegations. 

More details are accessible here.