NDP MLA David Eggen spoke to the crowd gathered Wednesday afternoon at a Red Deer park against the closure of the Michener Centre.
He says the NDP, the Wildrose and the Liberals stand together against the closing of the centre.
The Alberta government announced last month it plans to move 125 Michener residents to community group homes or seniors facilities.
Alberta Union of Provincial Employees president Guy Smith says the planned closure is another of Premier Alison Redford's broken promises.
Liberal Leader Raj Sherman told the crowd that the closure is a human issue, not a political issue.
"This is a test of the moral character and moral fibre of our government," Sherman said.
The province says the move into community homes by next spring and the closure of much of the facility will allow for more personalized care.
The union said 400 of its members who currently work at Michener Centre are to lose their jobs, be redeployed or retrained.
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