The head of Victoria Police's ethical standards body has resigned after being linked to racist YouTube comments.

Professional Standards Command head Brett Guerin was suspended and referred to the state's anti-corruption commission last week but quit the force on Monday night.

It comes after he admitted to using the alias 'Vernon Demerest' to make 'crude and coarse' comments about former colleagues online dating back to 2016.

Brett Guerin stepped down as assistant commissioner of Victoria Police on Monday night

Mr Guerin, who was appointed Assistant Commissioner in 2015, resigned after The Age reported Demerest also made racist remarks under YouTube videos.

'I'm afraid this is what happens when the lash is abolished. The jigaboo runs riot and out of control. The 'boo needs the lash. The 'boo wants the lash. Deep, deep down the 'boo knows the lash provides the governance and stability', the Age said Demerest wrote in response to a Somali pirate attack video.

Under a video about Argentina's loss to Holland in the 1998 World Cup, he said: 'Wonderful to see greasy, diving, cheating dagoes get their just reward. Bitter, lingering defeat'.

Mr Guerin publicly apologised last week for making graphic references to former police commissioner Christine Nixon and former police union boss Paul Mullett on a website.

Victoria Police headquarters

'It's crude and coarse language and, you know, what I'm most ashamed about is my mother and my daughters have read it now,' he told 3AW on Thursday.

'The language I used ... was completely inappropriate, embarrassing and I can understand people saying "what the hell is this bloke doing?".'

In a statement on Monday night, Victoria Police said Chief Commissioner Graham Ashton had accepted Mr Guerin's resignation following more than 40 years with the force.

Paul Mullett, former Victoria police union boss, was targeted in comments by Mr Guerin

Former police commissioner Christine Nixon was one of the former colleagues Mr Guerin allegedly attacked

It read: 'Assistant Commissioner Brett Guerin has tonight rendered his resignation from Victoria Police.

'The Chief Commissioner has accepted this resignation. This action is related to an ongoing IBAC investigation into recent conduct alleged against him.

'Assistant Commissioner Guerin's policing career has spanned more than four decades during which he served the community in numerous operational commands.'