What does an MP have to do to lose their job?

In 2007 David Cameron sacked Patrick Mercer "after making allegedly racist comments".  However David Cameron was in no doubt that Mr Mercer's comments were racist. Well Mr Mercer has again made the news and this time has quit the Tory whip. We should discover the reasons in the near future when Panorama is next on our screens.

So Mr Mercer made racist comments and lost his job as a minister but not as an MP. This time it looks like parliamentary rules have been broken. So how does a racist Tory MP who breaks parliamentary rules keep his job? Wouldn't the vast majority of people who don't work at Westminster lose their jobs? This time something has gone terribly wrong. Mr Mercer is no longer a Tory and has resigned the whip in order "to save my party embarrassment" but again he has held on to his job as an MP. How does he manage to keep going when others would be sacked?

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