1. At the outset, one party to an employment contract, the employer cannot unilaterally reduce the salary of the employee without the employee's consent. Employee consent is necessary for a reduction in salary. An employment contract cannot be unilaterally varied by one party without the consent of the other. If an employer attempts to reduce an employee’s salary without their consent, this will entitle the employee to take any of the following action:
2. This is a common legal principle and has been enshrined in legislation in the Equal Pay Act, 1970. There have been many judicial decisions on the point but all really only apply the Equal Pay Act principle of equality of position.
3. The most recent decision in the High Court on this point was in the case of Malone & ors v British Airways plc  EWHC 302 (QB)
where the issue arose whether all contracts of employment of BA cabin crew were covered by negotiations entered into in accordance with the collective bargaining provisions of the Trade Union Agreement. The issue arose whether BA could change all contracts of employment based on the outcome of the collective bargaining or whether individual consent of every worker was required. BA argued that it had the power to make unilateral variations to T&Cs of employment for most of the claimants due to an express variation clause included in its contracts since 1994. The High Court held that the collective bargaining and the express variation clause gave BA this power. On appeal to the Court of Appeal, the Court of Appeal declined to deal with this point.