Here’s a new feature PolitiFact is apparently rolling out for the 2016 campaign cycle: the fact-checking of predictions, or at least those made by GOP candidates. Today, for example, PolitiFact rated as “false” Sen. Marco Rubio’s assertion made Sunday morning on “Face the Nation” that cap-and-trade “would have a devastating impact on our economy.”

Rubio’s crime? Telling his host that “I can tell you with certainty” the economic effect of cap-and-trade. “Based on the evidence, Rubio can’t be certain about the potential impact of cap and trade,” PolitiFact concludes. He might very well be right — but he can’t be certain.