To be a good president, a candidate must be able to evaluate data. So early last year, I scored six likely Republican presidential candidates on their positions on seven science policy areas. The notion that the reality-TV star Donald Trump would actually run for president seemed farfetched at that point, so I didn't get around to evaluating his views until more recently. The seven policy topics were climate change, genetically modified crops, the Yucca Mountain nuclear waste facility, vaccination, fetal pain legislation, biological evolution, and a proposed ban on commercial travel from West African countries during the recent Ebola outbreak. So how do Gary Johnson and William Weld—the Libertarian Party's candidates for president and vice president, respectively—score with regard to the science policy issues? Pretty well.