Thus, I will address the alleged past practice before looking at the contract language. Were this to happen, the case could be decided without any reference whatsoever to the alleged past practice. The problem with this approach is that the Union sees this case, in part, as a past practice case. Thus, if I were to decide this case without reviewing the alleged past practice, I would not have addressed one of the Union's main contentions. I have therefore decided to use this unique structural format and review the Union's past practice contention in order to complete the record.
Past practice is a form of evidence commonly used or applied to clarify ambiguous contract language.
The rationale underlying its use is that the manner in which the parties have carried out the terms of their agreement in the past is indicative of the interpretation that should be given to the contract. Said another way, the actual practice under an agreement may yield reliable evidence of what a particular provision means. In order to be binding on both sides, an alleged past practice must be the mutually understood and accepted way of doing things over an extended period of time. Additionally, it must be understood by the parties that there is an obligation to continue doing things this way in the future. That said, the focus turns to whether the Union established the existence of a practice governing payment for travel time.