Democracy explained
After that point voting is made on party grounds and if there is any dissent, even if it is the will of the majority of the voters and if the member is likely to vote against the parties’ wishes, penalties can be enforced by using the parliamentary whip, or in cases where that is insufficient, by withdrawing the party whip, effectively taking the member out of the political party and resulting in their vote becoming almost useless.
In more serious cases the voters’ wishes are totally ignored and action can result in the member being sacked by the party.
DTA
Dronfield