The ACAS Arbitration Scheme (Great Britain) Order 2004

151.  Where the arbitrator finds that the Employee has unreasonably refused an offer by the Employer which (if accepted) would have the effect of reinstating the Employee in his or her employment in all respects as if he or she had not been dismissed, the arbitrator shall reduce or further reduce the basic amount to such extent as he or she considers just and equitable having regard to that finding.