In Britain recently, ninety-one Conservative MPs voted against a Conservative government bill to make the House of Lords elective, despite a "three-line whip," the strongest form of pressure for conformity the prime minister could apply. The bill passed because the opposition supported it, but without caucus support, Prime Minister Cameron seems to have agreed not to proceed with implementation.
Now this may be dumb policy or good policy, but it underlines how parliamentary democracy works. The leader answers to the caucus, not vice versa. And if a leader proceeds with too many policies the caucus dislikes, the caucus will probably replace the leader with someone more agreeable.
In a parliamentary democracy, the caucus has the power to make or unmake policies and leaders anytime it chooses. It's just that Canadian caucuses believe that they don't, and so they never choose to. Pity.
