Article 5 - Unilateral Changes

Past Practice

The following explanation represents the national parties’ general agreement on the subject of past practice. The explanation is not exhaustive, and is intended to provide the local parties general guidance on the subject. The local parties must insure that the facts surrounding a dispute in which past practice plays a part are surfaced and thoroughly developed so an informed decision can be made.


Article 5 may also limit the employer’s ability to take a unilateral action where a valid past practice exists. While most labor disputes can be resolved by application of the written language of the Agreement, it has long been recognized that the resolution of some disputes require the examination of the past practice of the parties.

Defining Past Practice

In a paper given to the National Academy of Arbitrators, Arbitrator Mittenthal described the elements required to establish a valid past practice:

• First, there should be clarity and consistency. A course of conduct which is vague and ambiguous or which has been contradicted as often as it has been followed can hardly qualify as a practice. But where those in the plant invariably respond the same way to a particular set of conditions, their conduct may very well ripen into a practice.
• Second, there should be longevity and repetition. A period of time has to elapse during which a consistent pattern of behavior emerges. Hence, one or two isolated instances of certain conduct do not ordinarily establish a practice. Just how frequently and over how long a period something must be done before it can be characterized as a practice is a matter of good judgment for which no formula can be devised.
• Third, there should be acceptability. The employees and supervisors alike must have knowledge of the particular conduct and must regard it as the correct and customary means of handling a situation. Such acceptability may frequently be implied from long acquiescence in a known course of conduct. Where this acquiescence does not exist, that is, where employees constantly protest a particular course of action through complaints and grievances, it is doubtful that any practice will be created.
• One must consider, too, the underlying circumstance which give a practice its true dimensions. A practice is no broader than the circumstances out of which it has arisen, although its scope can always be enlarged in the day-to-day administration of the agreement. No meaningful description of a practice can be made without mention of these circumstances. For instance, a work assignment practice which develops on the afternoon and midnight shifts and which is responsive to the peculiar needs for night work cannot be automatically extended to the day shift. The point is that every practice must be carefully related to its origin and purpose.
• Finally, the significance to be attributed to a practice may possibly be affected by whether or not it is supported by mutuality. Some practices are the product, either in their inception or in their application, of a joint understanding; others develop from choices made by theemployer in the exercise of its managerial discretion without any intention of a future commitment.

Heritage - Past Practice - Radios -1627 [...]
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