Politics and Law..

When you lie to, or attempt to deceive, a judge in a courtroom, it is called 'perjury', and it is a criminal offence.

When politicians do the same to their own people, should be called 'treachery'. And should they be prosecuted if caught?

Yup. No one should be above the law.

Depends on the lie. Generally people are stupid and/or ignorant and/or emotionaly led. A politician's job is to take care of the country, sometimes this is different to doing what is in the immediate best interests of the people ( e.g. going to war). I imagine lies would be neccassary in some circumstances. Of course most lies are probably told because it's in the interests of the lying scumbag politician, but that's a seperate issue.