Breach of the peace

Breach of the peace, or disturbing the peace, is a legal term used in constitutional law in English-speaking countries, and in a wider public order sense in the several jurisdictions of the United Kingdom.

In the United States, the Speech or Debate Clause of Article One of the United States Constitution provides that members of Congress shall be immune from arrest in going to and departing from sessions and while Congress is in session except for cases of "Treason, Felony, and Breach of the Peace."

The first two are somewhat self-explanatory; it has been suggested that the third is deliberately somewhat vague. The doctrine thus established is called congressional immunity; it arose out of the necessity to prevent a vengeful executive from arresting members of the legislature under a pretext to prevent them from taking actions that the executive might find to be displeasing. In recent years, this doctrine has been used to prevent members from being stopped and held for speeding on their way to sessions; this apparently is not a "breach of the peace", whereas perhaps another misdemeanor such as "drunk and disorderly" might be construed to be such.

Most states of the United States and most other English-speaking jurisdictions have extended this privilege to members of their legislatures on the theory outlined above.

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