I don't think it's possible(or perhaps just practical) to be a politician in any system and not lie at least some of the time. Even if you had a democracy, there's a very good chance that the populous hasn't the faintest clue of what they're talking about, in which case the politician's next course of action is to allow their constituency to hang themselves or to deviate from their proximal wishes knowing later down the road they will be better off. Simpler than that, it's usually not that practical to inform a population on all the nitty gritty details behind legislation, in which case you will inevitably get embellishments for the sake of moving things along, rather than allowing things to get held up because the 80% majority fails to grasp the issues.

>Even if you had a democracy, there's a very good chance that the populous hasn't the faintest clue of what they're talking about, in which case the politician's next course of action is to allow their constituency to hang themselves or to deviate from their proximal wishes knowing later down the road they will be better off.

It should not be their choice to act as if they "know better", and in actual democracies it couldn't be (they were taken out of duty and/or punished for such acts).

Besides, more often than not it's not about them "knowing better" but about giving in to this or that private interest of theirs, or lobby, or deep state, or military, or big donors, or under the table or "barely legal" deals ("Do this, and you'll come working for my company on a sinecure with good money after your term") and so on.

Which is why this 180-turn doesn't happen just on some newly emergent situations that the politician supossedly "has better information", but also for things the politician themselves and the party itself promised to do in its pre-election program.