A whip is the instruction issued (not always) by political parties to vote according to the party line in a legislature. Violation of the party whip could lead to expulsion under the Anti-Defection Act.
A whip is of three kinds:
- A one-line whip is non-binding, and merely serves to inform the members of the vote.
- A two-line whip seeks attendance in the legislature during the vote.
- A three-line whip is a clear-cut directive, to be present in the legislature during the vote and cast vote according to the party line. Violation of the whip could lead to the member’s expulsion from the House.
In India, under the anti-defection law, a three-line whip can be violated only by more than one-third of a party’s strength in the legislature.