It is easy to see why regulators often favour ambiguity over precision: make a rule too rigid and a loophole can easily be exploited.

But on the flip side of that argument, overly broad regulations can be interpreted to apply to anything and everything; or, equally as bad, hit the wrong target. In the case of the US Federal Energy Regulatory Commission’s (Ferc) approach to anti-manipulation enforcement actions, lawyers and market participants say there are too many shades of grey.

“There is a