The chairman of the House of Delegates is called the Speaker: he is chosen by the House of Delegates members after a party caucus. The chairman of the Senate is called the President of the Senate and the Lieutenant-Governor automatically serves as chairman. In the absence of the Lieutenant-Governor or whenever he finds it necessary to carry out the office of Governor, the Senate chooses a president pro tempore (president for-the-time-being) from its own membership. Each house of the General Assembly selects its own officers (Clerk, Sergeant-at-Arms, two Door Keepers), settles its rules of procedures and directs writs of election for filling vacancies which may occur during the General Assembly's session. If vacancies occur during the recess period when the General Assembly is not in session, the Governor may issue writs of election as prescribed by law. Each house is responsible for determining its own rules and for judging the election, qualifications, and returns of its own members; each house may punish its members for disorderly conduct and may expel a member whenever two-thirds of its members so concur. The members of the General Assembly are entitled to certain privileges. They are free from arrest during the session of their particular house except in cases of treason, felony (a serious crime) or breach of the peace. They cannot be questioned in any other place for any speech or debate in which they participate in either house. Furthermore, they are free from arrest under any civil process during the regular sessions of the General Assembly and during the fifteen days directly preceding or directly following the session. Each house of the General Assembly must keep a journal of its proceedings and must publish it from time to time. Whenever one-fifth of the members present express a desire to have the "yeas" and "nays" of their members on a specific question recorded, such information must be entered in the journal. The Clerk of each house has this important duty of journal-keeping. In addition, the Clerk also prepares the payroll, keeps the docket and supervises the printing of the legislative acts--hence, he is often called the "Keeper of the Rolls" of the Commonwealth. As mentioned earlier, the chief purpose of any legislative body is to make laws. In Virginia, every law must be introduced in the form of a bill. There are six major steps in the process whereby a bill becomes a law: (1) A bill may originate in either house. The legislator who sponsors it is called the "Patron." It is customary for all appropriation bills to be introduced in the House of Delegates; the Clerk of the house in which it originated assigns a number to it. No regular bill can be introduced after the beginning of the last three weeks of a session.