The worst case is that of Selwyn Leeks, the doctor who headed Lake Alice hospital's child and adolescent unit in the 1970s and has been accused of punishing patients with electric shock therapy.
Police here found there was insufficient evidence to lay criminal charges but Leeks was ordered by an Australian court in 2006 to pay $55,000 in damages for sexually abusing a former patient.
"He's never been brought to trial," says Marbrook, with evident disgust, "and that puts a lot of the stories into context. If he is seen as the epitome of the bad clinician and no one has thought there is enough evidence to charge him ... "
Marbrook's film is notable for its measured, unsensationalist tone and its focus on the survivors rather than the historical horrors. His camera dispassionately surveys the quasi-Victorian institutions with door signs such as "Calming and Restraint" and uses editing techniques to evoke the patients' states of mind.
But it's not simply a catalogue of victimhood; its subjects' stories are full of humour and hope. "I was really interested in these stories and wanted to tell them in a dignified way," he explains.
"The hope was that the different people that we had would tell very different and specific portions of the story that others couldn't tell. It was important to have someone whose partner could reflect on it, for example. It counters those initial thoughts in the viewer that, 'oh well, that person was psychotic and didn't know what was going on'. It was really important to see that journey through a psychiatric institution from the perspective of a couple who both have different takes on things."
Marbrook believes the acceptance of various mental illnesses has increased hugely over the past 40 years. People are much more aware about bipolar disorder, about depression, he says, and he hopes that the film will encourage viewers to think in a more nuanced way about all sorts of disability.
"I think there are wider messages out there about institutional levels of care. Once you lose sight of the person you're treating it's quite difficult. It's not just giving medication."
Lowdown
Who: Jim Marbrook, director documentary Mental Notes
What: World Cinema Showcase 2012
When: Screening today 6pm, tomorrow 1.50pm and Monday 11.30am, Rialto; Sunday April 8, 4pm, Bridgeway
-TimeOut