Should a serving prime minister today lose his or her seat in the legislature, or should a new prime minister be appointed without holding a seat, the typical process that follows is that a junior member in the governing political party will resign to allow the prime minister to run in the resulting by-election.[16] A safe seat is usually chosen; while the Liberal and Conservative parties traditionally observed a convention of not running a candidate against another party's new leader in the by-election, the New Democratic Party and smaller political parties typically do not follow the same convention.[17] However, if the governing party selects a new leader shortly before an election is due, and that new leader is not a member of the legislature, he or she will normally await the upcoming election before running for a seat in parliament.
如果一位现任总理今天失去了他或她在立法机构中的席位,或者如果任命了一位没有席位的新总理,通常的程序是,执政党中的一名初级成员将辞职,以便让总理参加由此产生的补选。通常会选择一个安全的席位;虽然自由党和保守党传统上遵守不让候选人在补选中与另一党的新领导人竞争的惯例,但新民主党和较小的政党通常不会遵循同样的惯例。然而,如果执政党在选举即将到来之前选出了一位新领导人,而该新领导人不是立法机构的成员,他或她通常会等待即将到来的选举,然后再竞选议会席位。