A ruling by the National Labor Relations Board on Tuesday -- changing the definition of which workers have enough supervisory roles to be disqualified from collective bargaining -- could hurt efforts to unionize faculty members.

The ruling, which involved a series of disputes over whether nurses with some supervisory roles are eligible for unions, may have no immediate impact for professors. The board ruled that nurses who perform functions like assigning duties to others, and setting shifts, are supervisors -- even if only a minority of their time is spent actually supervising. The ruling by the board was 3 to 2 and the dissenting members said that the standard set by the majority would make it very difficult to unionize professional workers because so many of them have some supervisory roles.

Leaders of unions had urged the board not to rule as it did and immediately denounced the ruling. A court battle is possible. Leaders of academic unions said that the reason it would have relatively little impact at least in the short term is that the NLRB -- which only governs unionization of private colleges, not publics -- has already severely limited collective bargaining for faculty members. Under the NLRB's interpretation of various court rulings -- an interpretation rejected by many labor activists in academe -- it is the rare private college faculty that could unionize.

For those few private colleges that can unionize now -- or if court rulings are reversed and private college faculties are later given that right -- the new ruling could be problematic. A spokeswoman for the American Federation of Teachers said that faculty members who supervise a laboratory or junior faculty members might be excluded from bargaining units. In the dissent, two NLRB members specifically said that they feared the majority ruling would make a teacher who supervised an aide ineligible for collective bargaining.

Michael Mauer, a labor lawyer who is director of organizing and services for the American Association of University Professors, said that another fear was that the NLRB ruling could "embolden certain public sector administrations and boards." Labor law for public institutions is governed at the state level, and there is no requirement that any state follow the NLRB's lead. In many states, public colleges and universities have unionized faculty members and professors engaged in collective bargaining that the NLRB would reject. But Mauer and others also said that some state boards do pay attention to the NLRB and this ruling could give union opponents a new strategy.

Michael Simpson, assistant general counsel for the National Education Association, called the decision "horrible" and said there was one sad irony for faculty members who back unions. If the NLRB challenges faculty union members because they supervise teaching assistants, Simpson said that they could cite another NLRB ruling (also opposed by unions) that TA's are students, not employees.