The Speaker pro tem of the Lok Sabha is appointed by the:

When a new Lok Sabha is constituted, the Speaker of the previous House vacates office immediately before its first meeting. The President then appoints a member of the new Lok Sabha as the Speaker pro tem.

Choice of the pro tem Speaker:

• Usually, the senior-most member of the new House, in terms of years of service in the Lok Sabha, is chosen.
• The choice is made on the advice of the government, through the Ministry of Parliamentary Affairs.

Oath:

The President himself administers the oath to the Speaker pro tem.

Functions of the pro tem Speaker:

• He administers the oath to the newly elected members.
• He enables the House to elect the new Speaker.
• He has all the powers of the Speaker while he holds the office.
• His office ends when the new Speaker is elected.

Meaning of "pro tem":

• "Pro tempore" is a Latin phrase meaning "for the time being".
• So the office is temporary.

Constitutional basis:

• Article 95(1) provides that when the office of Speaker is vacant, the Deputy Speaker or, if that office is also vacant, a member appointed by the President shall perform the duties of the Speaker.
• The pro tem Speaker system is based on this provision and on parliamentary practice.

Controversies:

Sometimes a member who is not the senior-most has been appointed pro tem Speaker, leading to objections from opposition parties.

State legislatures:

• In the states, the Governor appoints the pro tem Speaker of a newly elected Legislative Assembly.
• The pro tem Speaker plays an important role, especially when a floor test is held before the regular Speaker is elected.
• The Supreme Court has sometimes directed that floor tests be held under the pro tem Speaker to avoid delay.

Election of the Speaker:

The new Speaker is elected by a simple majority of members present and voting.

Why not the other options?

• ✗The Prime Minister advises but does not appoint.
• ✗The Chief Justice of India and the outgoing Speaker have no role.