Past Practice
A consistent, long-standing workplace custom that becomes binding even if not written in the CBA.
Full definition
A past practice is an established, repeated, and accepted way of doing things in the workplace that — over time — becomes enforceable as if it were part of the CBA. Arbitrators generally require that a past practice be (1) unequivocal, (2) clearly enunciated and acted upon, (3) readily ascertainable over a reasonable period, and (4) accepted by both parties. Past practice is most powerful when the CBA is silent on the issue; it cannot generally override clear contract language. A change to a long-standing past practice without bargaining can itself be the basis of a grievance or an unfair labor practice charge.
Related terms
Collective Bargaining Agreement (CBA)
A legally binding contract negotiated between a union and an employer that governs wages, hours, and conditions of employment.
Grievance
A formal complaint that the employer has violated a provision of the CBA, past practice, or applicable law.
Unfair Labor Practice (ULP)
Conduct by an employer or a union that violates Section 8 of the National Labor Relations Act.
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