III. The Bundestag
Article 46
[Immunities of Members]
(1) At no time may a Member be subjected to court proceed¬ings or disciplinary action or otherwise called to account outside the Bundestag for a vote cast or for any speech or debate in the Bundestag or in any of its committees. This provision shall not apply to defamatory insults.
(2) A Member may not be called to account or arrested for a punishable offence without permission of the Bundestag, unless he is apprehended while committing the offence or in the course of the following day.
(3) The permission of the Bundestag shall also be required for any other restriction of a Member’s freedom of the person or for the initiation of proceedings against a Member under Article 18.
(4) Any criminal proceedings or any proceedings under Article 18 against a Member and any detention or other restriction of the freedom of his person shall be suspended at the de¬mand of the Bundestag.
State privileges and immunities
Immunity - national proceedings
EDIT.