The Allan Labor government in Victoria is being advised on its industrial relations strategy by a senior manager of major construction firm Multiplex who is in a relationship with a high-ranking CFMEU official being investigated by police for alleged corruption.

Six construction industry and union sources, who mostly spoke on the condition of anonymity citing fear of repercussions, have raised concerns about the potential for conflicts of interest to arise from the relationship between Multiplex construction manager Amy Pitchford, and embattled construction union assistant secretary Derek Christopher.