What should be clear is that the very label “dark money,” whether it can be adequately defined or not, is intended as a pejorative to skew the difficult discussion about political speech and participation, government power, and the influence of money and wealthy donors. It’s handy and catchy, so it sticks, but it is not, and is not intended to be, a neutral description. And it’s definition is indeed malleable, so that the merry regulators can use it as they please. When they think a number sounds scary, they use it, as if “dark money” were some clearly defined and measurable concept. When their own numbers are turned back on them (as in pointing out that it is a very small part of total spending), “dark money” again becomes a vague concept, in which no one can know what is lurking below the surface, like some malevolent iceberg or killer shark.