Party lines - Definition and Overview

Most political parties in Western democracies have policies on a range of issues. When legislation is proposed in the legislative body (parliament, congress, &c.) on certain subjects important to a party, all members of the party are expected to vote the same way, or face the anger of, or even expulsion from, the party. This is known as 'following the party line'.

On other occasions, members are free to vote as their conscience permits, this is known as a conscience vote.