Disability advocates have expressed outrage at revelations an intellectually disabled man judged unfit to face criminal charges was effectively detained in permanent solitary confinement for six years.

The case of Adrian, whose real name has been suppressed to protect his identity, is contained in a scathing report by the Queensland ombudsman into the state’s forensic disability services system.

Phil Clarke’s report accuses authorities of “widespread legislative non-compliance” at the medium secure 10-bed facility at Wacol in Brisbane (the FDS) and makes 15 recommendations, including an end to the use of police dogs for behaviour control.

Clarke drew specific attention to the case of Adrian, who was held in seclusion 99% of the time between 24 September 2012 and 18 June 2018, according to the report tabled in state parliament last week.

The investigation concluded “the approach to secluding Adrian has been contrary to law, unreasonable, oppressive and improperly discriminatory” and raised “human rights concerns, including indicators of systemic abuse”.

Police were called and officers used dogs to subdue Adrian because he was “petrified” of the animals, according to staff notes, and in one instance he was found “crying in the foetal position” after one was sent into his unit.

Jeff Smith, the chief executive of People with Disability Australia, told Guardian Australia: “This is an outrageous case of a person with disability being held in solitary confinement for many years, causing immense harm to him.”

Seclusion orders signed ‘retrospectively’

The specialised Wacol facility was built in an overhaul of forensic disability services by Anna Bligh’s Labor government in 2011.

Seclusion orders are designed to protect clients and staff from “imminent physical harm” where no “less restrictive” option is available.

Under the legislation, they must be authorised by a senior practitioner and can only last a maximum of three hours at a time.

Clarke acknowledged staff were not “comfortable breaking seclusion due to concerns for their personal safety” and that authorities considered him a “very challenging individual with complex and dangerous behaviours” who had caused significant damage to the facility.

Still, the ombudsman found authorities had failed to meet the legislative requirements and that the length of time Adrian had “been in seclusion may have significantly harmful effects on his wellbeing”.

Analysis of a portion of the 18,000 orders issued for Adrian contained “a high degree of repetition of words used to describe the presenting risk” and sometimes appeared to be “pre-populated”.

Coralee O’Rourke says she shares the concerns of the ombudsman about Adrian’s case. Photograph: Dave Hunt/AAP

Orders were sometimes “signed by a senior practitioner retrospectively”, according to staff, or issued despite notes showing the risk was “currently low”.

The ombudsman was also concerned that CCTV footage was not retained, as “required by relevant legislation and policies”.

Adrian’s life at the FDS

In his early childhood, Adrian was diagnosed with an intellectual disability and a form of chromosomal disorder and suffered “significant emotional, physical and sexual abuse both at home and by carers in out-of-home care”.

In 2012, he was charged with “serious criminal offences” but found unfit for trial and the charges were dropped.

Adrian was placed in a “seclusion unit that had been specifically constructed” for him that includes a living area, bedroom and shower and toilet, and small concrete undercover yard.

Staff communicate with Adrian through a “narrow horizontal slot through which meals and other items are passed” and will cover the slot, “removing all capacity for human contact” if his behaviour escalates.

On five occasions, he has been charged by police with criminal offences against staff, but the charges were later dismissed, struck out or withdrawn due to his condition.

He also slept for up to six months in a “tent-like structure” he built in his concrete courtyard area “using ropes and a tarp provided by … management for this purpose”.

Adrian built the structure to protect his privacy, but “the mattress inside was putrid and mouldy” and was later removed by the police, the report said.

He now refuses seclusion breaks because of his “lack of self-determination as a person”, with staff concerned for his overall health. It was noted he sometimes misses meals for several days.

Response from authorities

Queensland’s minister for disability services, Coralee O’Rourke, told Guardian Australia she shared the concerns of the ombudsman about Adrian’s case and that the recommendations were under review.

“I am advised that over the past 12 months the FDS has put strategies in place to encourage and enable this client to participate safely in activities outside his rooms to reduce his seclusion and support his rehabilitation,” she said.

O’Rourke said the use of police dogs in the facility was an “operational matter for the Queensland police service” and had been referred to the police commissioner.

She said there were already reforms underway to build staffing capacity and hand more powers to the director of forensic disability, who oversees the system. A search was also underway for a new director and a new administrator of the FDS had also been appointed.

A spokeswoman for the department said it “acknowledges the ombudsman’s concerns about the seclusion of a client”.

“A series of independent clinicians, the mental health court and reviews by the mental health review tribunal have confirmed the ongoing need for detainment due to the risk this client presents to himself and others,” she said.