Southern District Commander Superintendent Paul Basham confirmed the complaint had been received two weeks ago.
After the complaint was received "an employment investigation commenced and the staff member was moved from their position within 24 hours", Basham said.
"The individual is under close supervision in a non victim-facing role. The investigation is being headed by a senior investigator."
He said he wanted to reassure the public complaints about police employees were taken "extremely seriously".
"All staff are bound by the Police Code of Conduct."
Basham was limited in what he could say as the investigation was continuing, he said.