When should lying be tolerated by the government?

[TomCollins]

I got into an interesting debate with a friend about the role of lying in politics.

He had the belief that lying is a natural part of politics, and is perfectly permissible if the ends justify the means. An extreme example is if you believe that stopping illegal immigration is a key priority, making up false intelligence that terrorists are planning to cross the border, so we need to build walls with electric wire and deploy the army.

I tend to believe that lying should only be used in extreme cases, such as immediate national security, protecting foreign agents, etc... I can't really put up a good litmus test, but would prefer my government lie to me only when it absolutely must (if a girl asks me if she looks fat in a dress, I'm certainly going to tell her no).

On the other end, some may argue that no lying is ever appropriate.

Is there any kind of litmus test you can apply to when it is acceptable for a goverment to lie? Of course, this is all subjective and personal opinion.