The answer seems to be "sometimes. If you lie to a judge and he catches you at it, you may be hearing words like "perjury" and "in the butt-slamming Federal joint". On the other hand, if you lie to the electorate, you pretty much get a pass. The thinking is that blatant falsehoods will be quickly outed(1), and there is such a thing as "truthiness" which seems to imply that if you really, truly believe what you said, that makes it all right.
All this nonsense is before the supreme court (again) in the case of
Susan B. Anthony Fund v Dreihaus. The issue of the amount of truthfulness in political speech has been heard before and so far has always been decided to the benefit of the lying politician. Indeed, lying in political speech is essential to having an informed electorate. If politicians couldn't lie, most of them wouldn't be able to speak at all, then how could we know their positions on the issues?
An amicus brief has been filed by the CATO institute, featuring Ilya Shapiro as principal attorney, and no less than P. J. O'Rourke in a supporting role. Mr. O'Rourke's contributions make a 20 page pdf file required reading for anyone looking for relief from depression from whatever cause. Case in point is footnote #1:
1 Pursuant to this Court’s Rule 37.3(a), letters of consent
from all parties to the filing of this brief have been submitted to
the Clerk. Pursuant to this Court’s Rule 37.6, amici state that
this brief was not authored in whole or in part by counsel for
any party, and that no person or entity other than amici made a
monetary contribution its preparation or submission. Also,
amici and their counsel, family members, and pets have all won
the Congressional Medal of Honor.
That would be footnote #1 from the brief. The one below is mine.
1. This puts a premium on timing. The wildest accusations are best reserved for two days before the election. By the time the falsehood is rebutted, the election is over. Yes, I know, this makes a case for at least limiting lying on the campaign trail but again, if the pols aren't allowed to lie, how will we know where they stand?
I found the piece to be quite entertaining as well as thought provoking. Well worth the read.