Victoria's police union says it is not a "total shock" that the anti-corruption watchdog found evidence of drug use and trafficking among cops.
An Independent Broad-based Anti-corruption Commission special report found officers were partying on ice, cocaine and ecstasy, would meet up with known traffickers, and peddle drugs themselves.
Police Association of Victoria secretary Ron Iddles said there was no systematic problem, but it was not a surprise some police were involved with drugs.
"Our members are susceptible to more pressure and stress than the average member of society," Mr Iddles said in a statement to AAP.
The report looked at three investigations into claims of drug possession, trafficking and use by police since 2014 and said allegations against eight officers have been substantiated.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Operation Apsley revealed a group of police were using drugs regularly in their social lives - including one who used cocaine "most days" for four months last year.
Two other IBAC operations also exposed regular drug use, with one that focused on a constable leading to that officer's brother being arrested by federal and interstate police on drug offences.
While IBAC says allegations against eight were substantiated, it says they were likely just "snapshots of a more widespread and serious problem for Victoria Police".
On Wednesday, IBAC will launch a behaviour change campaign to encourage Victorians to report public sector corruption.
"Corruption results in wastage of taxpayer money, loss of goods and services, reduction in community confidence in public authorities," IBAC said in a statement.
"(That includes) state government agencies, departments and local councils, and adversely impacts on honest businesses that miss out on government contracts."
