I'm assuming you're trying to corner a point of "You cannot cite a specific law because it doesn't exist" without outright saying it.

It seems plain that, at best, Robinhood has violated its fiduciary, and at worst manipulated the market. This is one of those things I've come to understand as being illegal in the same way that I know insider trading is illegal. No, I cannot cite which law makes insider trading illegal.

Maybe you're right and there is no law. I personally don't have the time or experience to go digging through legal text to treat HN like an official courthouse. We will know by the results of the lawsuits, or by a video from the Legal Eagle on YouTube.