WorkSafe Victoria is investigating a complaint that Victoria Police and Chief Commissioner Graham Ashton allegedly failed to protect employees from a senior officer accused of repeatedly bullying colleagues.

A recent complaint to Victoria's workplace watchdog has accused Mr Ashton of ignoring the recommendations of a report into the alleged conduct of former superintendent Dean Stevenson in 2012.

Former Victoria Police commander Dean Stevenson. Credit:Simon O'Dwyer

Mr Ashton, who was then deputy commissioner, ordered a new probe that allowed the former high-ranking officer to remain in the job, according to a complaint by former officer David Bishop, who was an alleged victim of Mr Stevenson.

Mr Stevenson was later promoted to the rank of commander but resigned last year after he was accused of bullying at least five other officers, which prompted the force to undertake an occupational health and safety risk assessment of his conduct.