The new arrangement threatens eight peak bodies, with 200,000 members.The former chairman of the United Nations committee representing people with disabilities has added his voice to the chorus of anger over the government's shake-up of the sector, challenging its claim it is in acting in accordance with the UN convention.Ron McCallum, who is blind, is a former dean of law at Sydney University and, until December, was chair of the United Nations Committee on the Rights of Disabled Persons in Geneva.