Bill Gould was quoted in the Daily Journal in an article (found below) about the National Labor Relations Board. The article discusses the concept of "supervisory role" in terms of Labor Relations.
Supervisory status, apparently, is determined by detailed scrutiny of job duties, assigned tasks, and accountability. At bottom, the board's test comes down to defining employee loyalty: Which side are you on? "We've been in a no-man's land for 60 years," says William B. Gould IV, a professor at Stanford Law School and former chair of the NLRB. "The irony is that ever since Taft-Hartley, we've been moving toward a workforce that can think for itself, and away from checking your brains at the factory gate. We want charge nurses to think for themselves."