[4] The deviations might be countered by consequences ("whipping"[3]) that are designed to ensure the relative cohesion of members of the respective party group.
[15] Party discipline tends to be increasingly strong in countries that employ the Westminster parliamentary system, such as the United Kingdom, Canada, Australia, New Zealand.
[17] Within the United Kingdom, the devolved Scottish Parliament uses the mixed member proportionality system of voting and so party discipline tends to be high.
However research does show that proportional voting systems do result in constituent representatives engaging more with their respective ridings while regional (list) MP's often spend more time legislating.
This can also be seen in Republican failures to repeal Obamacare and the general power wielded by senators with a pivotal vote, such as Joe Manchin and Kyrsten Sinema during the 117th Congress.
An independent evaluation found that MPs in the Canadian House of Commons voted the party line 99.6 percent of the time between 2015 and 2019.
[23] Canadian MP's also face intense pressure to toe the line when making public remarks inside and outside the legislature.
This group discipline has registered an oscillation from strong to weak over the years, defined as a pendulum, depending on the political phase of the government.
[24] In Australia the electoral conditions can result in candidates from one of the minor parties or a microparty, elected to government with extremely small vote numbers.
An example of this is Jacqui Lambie, who won election to the federal senate in 2013 with the Palmer United Party, then quit to start a microparty under her own name only four months later, winning another term after a double dissolution.
[25] While the brand ambassador phenomenon does work to ensure the smooth operation of democracy, it also has several criticism, such as the oppression of dissenting opinions.
[25] This proverbial prohibition of those who deviate from the norm in establishment politics includes its tendency to suppress the representation of women and minority members of the party.
Research from a variety of global legislatures has indicated that parties tend to only select women and minorities who are extremely partisan loyal.
Examples of this behaviour include the expulsion of former attorney general Jody Wilson-Raybould from the Liberal Party of Canada in response to her pursuit of criminal proceedings in the SNC Lavalin scandal.
Parties often view minority candidates as simple brand ambassadors that check social diversity quotas which has been shown to impair these members from ever doing anything substantive.