A police superintendent who allegedly discriminated against gay officers complained that one may have illegally and secretly recorded him, one day after learning of allegations by the gay officer, a tribunal has heard.

Newtown Local Area Command officers Steven Rapisarda, Christian McDonald, Shane Housego and Christopher Sheehy were covertly investigated for six months in 2015, suspected of drug use.

Christopher Sheehy (left) receives a bravery award from Newtown Police Commander Simon Hardman in September 2015. The young officer was being covertly monitored during the same period on the recommendation of his boss.

The probe, which found nothing, was set up after their superintendent, Simon Hardman, complained that two of the "tight-knit group of like-minded homosexual" men were notorious for their promiscuity and drug taking may be linked to their "indiscriminate sexual encounters".

Mr Hardman said two of the officers had shaved their hair, possibly to avoid drug testing, and had suspicious sick leave patterns.