The Washington Post decided to publish an article by the least credible person in America on the importance of White House officials speaking the truth. They seem to be completely oblivious to the irony of having Susan Rice lecture us on this question.
Credibility is the currency in rhetoric, and Rice could not be less credible than she is. However, there's more to life than rhetoric. Philosophically, it is improper to dismiss her simply because she is a hypocrite who is manifestly guilty of the same offense -- or an even worse one, as her lies were carefully planned. That would be the logical fallacy of tu quoque, combined with the fallacy of ad hominem. She might have a point, even though she's a horrible person and a hypocrite.
And, indeed, she does have a point. Honor holds the world together. Truth is a force multiplier. Those things are true, whoever says them.