MADISON, Wis. (AP) -- The state Supreme Court says an Alzheimer's patient was improperly committed.

The case involves an 85-year-old woman who suffers from Alzheimer's disease. A judge in 2010 granted Fond du Lac County's request under Chapter 51 to place her in a locked psychiatric unit because she couldn't cooperate with health care providers at a nursing home.

Chapter 51 statutes allow officials to detain mentally ill people in any mental health facility if their problems are treatable.

The Supreme Court ruled Friday that Chapter 51 doesn't apply to Alzheimer's patients because the disease is irreversible. The court said the woman could be ordered to a nursing home.

Fond du Lac County attorney William Bendt says the court doesn't mention how to help someone who can't cooperate with her medical providers.

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