More in the cross-post on the MRC's NewsBusters blog.
On his Tuesday MSNBC show, host Thomas Roberts scolded Republicans for sending a letter to Iran objecting to the ongoing nuclear negotiations: "Certainly there's great politics at play here in dealing with the President's foreign policy....So this is another jab at the President's foreign policy, of trying to undercut it. What's the precedent, though, of a letter like this?"
Sahil Kapur of the liberal Talking Points Memo blog responded to that question by making a completely false statement: "Thomas, I'm not aware of any precedent....I'm not aware of any precedent....It's extraordinary in the sense that this is very unusual. I can't remember the last time, certainly not in my lifetime, that members of Congress tried – sent a letter to a foreign government pretty openly trying to undermine a sitting President's negotiations."