Facts:

The respondent was initially employed by Cooperative Bank Plc as an Account Clerk and rose through promotions to the position of Officer. In 2005, inspectors from the bank’s Head Office audited the Oyo Branch and discovered that between 2004 and 2005, during the respondent’s tenure as acting Treasury Officer, some senior officers, including the respondent, defrauded the bank of ₦16.8 million.

The bank issued a query to the respondent regarding the fraudulent conversion of stolen cheques totaling ₦16.8 million for the benefit of Miss Afolabi Dorcas Folashade’s savings account at the Oyo Branch. The query stated that the respondent participated in a scheme of fraudulent withdrawals. In his handwritten response, the respondent denied involvement in the fraud and promised to be more vigilant and report irregularities in the future. Despite this, the bank later awarded him the 2005 Long Service Award and responded to his query with a caution and advice to be more responsible. Following the merger of Cooperative Bank with Skye Bank to form Skye Bank Plc, the respondent was sent for Resident Internal Control Officer training. Upon completion, he was transferred to the Inspectorate Department in that role.

Subsequently, the appellant dismissed the respondent for fraudulent conversion of ₦1.8 million for the benefit of Miss Afolabi Dorcas Folashade, citing recent investigations. The letter of dismissal described him as fraudulent, untrustworthy, and unfit for employment in a financial institution. The respondent filed an action at the High Court of Oyo State, seeking a declaration that the dismissal was illegal, unconstitutional, null, and void, along with claims for salaries, allowances, and other benefits. The appellant counterclaimed for funds advanced to the respondent.

After trial, the High Court held that the dismissal was wrongful but effective, awarding the respondent one month’s salary in lieu of notice and dismissing the counterclaim. Dissatisfied, the respondent appealed to the Court of Appeal, which allowed the appeal. It held that the employer, having already cautioned, rewarded, and reassigned the respondent based on the same facts, was estopped from subsequently dismissing him on those same grounds. The Court of Appeal set aside the one-month salary award and ordered payment of all entitlements up to the date the suit was filed. Aggrieved, the appellant further appealed to the Supreme Court.