No one can sue without a writ.

Explanation

(English-origin maxim.) A writ is the indispensable foundation of every lawsuit — without proper originating process, the court has no authority to hear the case.

Where this applies

• A man who shows up at the courthouse demanding that the judge hear his complaint is turned away because he never filed a writ or petition to initiate the case.
• A creditor's attempt to collect a debt is dismissed because she never filed the originating papers required to start the lawsuit.
• A citizen's challenge to a government action is rejected because no formal writ or bill was ever filed with the court — you cannot sue without proper process.