The state-law process by which a person can be held and treated in a psychiatric facility against their will - the emergency hold, the court hearing, the standard of dangerousness, and the constitutional limits on all three.
Civil commitment is the involuntary hospitalisation of a person for mental illness. It is a civil proceeding, not a criminal one, and it has two typical stages. An emergency hold allows a physician, a mental-health professional, or in some states a police officer, to detain a person for a short period set by statute for evaluation, on a finding that the person appears to be mentally ill and, because of it, a danger to themselves or others or unable to meet their basic needs. Holding the person beyond that period requires a petition to a court, a hearing at which the person is entitled to notice, to be present and to counsel, and a judicial finding that the statutory standard is met.
The standard is set by each state within constitutional limits. The Supreme Court has held that a state cannot confine a person who is not dangerous and is capable of living safely in the community, and that the facts justifying commitment must be proved by at least clear and convincing evidence - a higher standard than the ordinary civil one. Most states require a recent act or threat as evidence of danger; a growing number also allow commitment on a "grave disability" standard for a person who cannot provide for their own food, shelter or safety, and many now have outpatient commitment, under which a court orders treatment in the community rather than confinement.
Being committed is not the same as being found incompetent to make treatment decisions, and in most states a committed patient retains the right to refuse medication except in an emergency or after a separate determination. Commitment also carries collateral consequences the statute does not mention: a federal prohibition on possessing firearms after a formal commitment (not an emergency hold), and effects on professional licensing and some employment. A person subject to a hold or a petition has the right to a lawyer and, in most states, to an appointed one if they cannot afford counsel.
A person facing a commitment petition should have a lawyer at the hearing, and the state will usually appoint one; a family member who wants to help should ask the facility for the hearing date and the name of counsel rather than trying to argue the case. For families on the other side - trying to get treatment for someone who refuses it - a lawyer or the county mental-health authority can explain what the state's standard actually requires and what evidence a petition needs, which is very often the reason a first petition fails.
Choose your state. Each link opens the directory page for the city in that state with the most currently published law firms in this practice area; a +n beside the city is how many other cities in the state also have one. The list is generated when this page loads, so a state whose listings have lapsed drops out rather than becoming a dead link.