For Tim Chan, who is unable to speak, facilitated communication is “a lifeline” that allows him to do things he once thought impossible, such as socialising, or studying for his PhD. “I was presumed incompetent, and ignored or dismissed,” the 29-year-old, who was diagnosed with autism as a toddler, says using a text-to-voice tool in his home in Melbourne. Facilitated communication involves someone guiding the hand, arm or back of a non-verbal person, so that they can point to letters or words on a bespoke keyboard.

Mr Chan’s facilitator is his mother Sarah, and, over the past 20 years, her support has “faded” to a slight touch of his shoulder, which he says keeps him “focused”. Advocates insist it is a miracle tool, one which gives disabled people a voice. But a growing chorus of experts, families and even former facilitators want it banned, due to research indicating that the likely author of the messages is the facilitator, not the communicator.

They cite a string of criminal allegations made by non-verbal people using the method which have been dismissed by the courts and investigators. The debate has sparked allegations of ableism, ruined legacies, inspired a new Louis Theroux documentary, and an international conversation about the power dynamics between disabled people and those who care for them. Facilitated communication was created in 1977 by Australian disability advocate Rosemary Crossley, who died last year and left a complex legacy.

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