Disputes over whether a proposal is nonnegotiable because (a) it is inconsistent with laws, rules, and regulations establishing conditions of employment and/or (b) it interferes with, and does not constitute a § 7106(b) exception to, the exercise of rights reserved to management by § 7106.
Negotiability disputes normally are processed under FLRA's "no fault" negotiability procedures -- see § 7117(c)(1) and 5 CFR Part 2424. They can also be processed under FLRA's unfair labor practice procedures (5 CFR Part 2423) if they are associated with changes in conditions of employment in which management has refused to bargain on the union's proposals on the ground they are nonnegotiable. (If the union files under both procedures, FLRA will dismiss, without prejudice, the negotiability petition for review. See 5 CFR 2424.30(a).)
Negotiability disputes have played a prominent role in Federal sector negotiations because of the extent to which conditions of employment of Federal employees are determined by laws and regulations, with the result that there is far less room for bargaining than there is, e.g., in the private sector. The parties are, in effect, limited to bargaining in the interstices. Lack of clarity as to the meaning of management's § 7106 rights, as well as the complications brought about by § 7106(b)'s exceptions to those rights, also contributes to the high incidence of negotiability disputes.
Finally, when union-management relations are adversarial, there is a temptation to avoid bargaining by alleging that proposals are nonnegotiable rather than finding out what concerns or problems prompted the proposals and using the bargaining process as an attempt to find mutually satisfactory solutions to real problems. When the legal constraints are numerous, unclear, complicated (because, e.g., of exceptions and the need to use fact-sensitive balancing tests) and constantly changing, opportunities to make use of such tactics are abundant. Even when these constraints are not exploited to avoid bargaining, good faith assertions of nonnegotiability cannot help but create frustration and distrust. One of the virtues of interest-based bargaining is that issues of negotiability come at the end of the process, when evaluating alternatives, rather than at the beginning of the process, before interests and exploration of ways in which they can be met, are discussed.