A petition is a formal written request asking a court to take a specific action, like starting a case or getting an order.
It is the document you file to initiate many types of legal proceedings, such as family court matters or probate, instead of a complaint. The petition states the facts of your situation and what you want the court to do, and it is typically the first paper served on the other party. In a pending case, a petition can also be used mid-case to ask for emergency relief or modification of an existing order.
Filing a proper petition is often the legally required step to get the court’s attention and start official proceedings. If your petition is incomplete or incorrectly served, the court may dismiss your request before ever considering the merits of your situation.
Many people confuse a petition with a motion, but a motion is a request made within an already active case, while a petition usually opens or formally requests a new court action. Also, a petition is not simply a complaint or a letter; it must follow specific formatting and procedural rules, which vary by state and court.
Get the actual rule
This page explains the concept. When it matters to your case, read the rule that governs it in your court — we hold Texas, federal and Washington court rules word for word, and every state's official resources are on the state pages. If someone cites a case at you, check that it exists first.
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General explanation, not legal advice, and not specific to any state — procedures and deadlines vary by jurisdiction and court. If you can get a lawyer or free legal aid, do: every real option.