The State of Arizona has very lenient laws regarding involuntary commitment.

Arizona has one of the least restrictive laws when it comes to detaining apparently mentally ill people against their will. Under the state's broad involuntary-commitment statute, the government can mandate in-patient treatment for anyone determined to be "persistently or acutely disabled." That could include a broad range of seemingly troubled individuals. By comparison, many other states limit involuntary commitment only to people shown to be a danger to themselves or others, or who are found to be completely unable to take care of themselves.
Arizona also goes farther than many other states in defining who may initiate involuntary-commitment proceedings. In Arizona, virtually anyone who had suspected that Loughner had mental problems and needed help could have filed an application to a state-licensed healthcare agency for a court-ordered evaluation. Some states require that the application be initiated by someone close to the troubled person, among other discrete categories.
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