"In determining whether a policy adopted by management unilaterally has become a term of the employee's contract on the grounds that it is an established custom and practice, the factors referred to by Brown-Wilkinson J in Duke v Reliance Systems[1982] IRLR 347 EAT , whether the policy has been drawn to the attention of the employees by the management or had been followed without exception for a substantial period, are likely to be among the most important circumstances to be taken into account, but they have to be taken into account along with all the other circumstances of the case. The question is not whether the period for which a policy has been followed is "substantial" in the abstract sense but whether, in relation to other circumstances, it is sufficient to support the inference that the policy has achieved the status of a contractual term. With regard to communication, the question is not so much whether the policy was made known directly to the employees or became known through intermediaries, but whether the circumstances in which it was made or has become known support the inference that the employers intended to become contractually bound by it."
"22 For his part, the chairman had difficulty in reconciling the authorities with the applicant's case on the enhanced redundancy pay. For their part, the lay members, applying their industrial experience, had no difficulty whatsoever in seeing that this was a case in which not only was there a policy to make an enhanced redundancy payment in every case, but the policy bound the respondent as a matter of contractual obligation. They based their judgment on the period time over which, and the frequency with which, the enhancement had been paid. The fact that it had been conceded every time gave rise to the inference that, in reality, the respondent recognised that it had an obligation to make the enhanced payment. What changed in the applicant's case was the take-over by Weir plc and the instruction to Mrs Pilkington not to pay in his case."
"……having asserted the 1983 agreement, it [i.e Warman] felt obliged to pay. The threat of industrial action was a further inducement."